What the DNA says

The finding Inferred, strongly

Kurt Israel Luwinski is very probably not Lynn Derrick Luwinski's biological father. Two independent lines of evidence say so, and the paper record was already hinting at it before any test was taken.

Not documented, and not closed. What would close it is set out at the foot of this page.

Nor does de Witt obviously fit

The temptation is to move the fatherhood four months earlier and be done. But an Afrikaner Oelofse–van Straaten line should read Dutch, German and French Huguenot. The observed Dutch is 1.5% and Germanic 1.4%, against English 18.5% and a named genetic group of Southeastern and Eastern England. That is an English family, not a Cape one. The question is open, and this archive does not intend to close it by guessing.

And one match is a generation closer The lead

The 297.5 cM match is not part of that knot — to her, the Harrison line is only a parent's third cousin. She sits nearer to Derrick than any of them:

1st cousin's daughter — 39.7% — most recent common ancestors: Derrick's grandparents.

In plain terms: her grandparent was a sibling of Derrick's biological father. And the detail that turns arithmetic into a place — her father was born in Johannesburg. Her family surnames are Halsey, Parr and Fenton.

Chromosome 2, 181,681,048 – 216,191,586 34.5 Mb

All three matches share that exact stretch with Derrick.

And a recombination you can see

On chromosome 18 one match's segment ends at 55,491,965 and the other's begins at 55,493,868. They abut, 1,903 base pairs apart. Two relatives holding adjacent, non-overlapping stretches of the same ancestral chromosome is the signature of a break in a shared ancestor — the point where one grandparent's chromosome was cut and handed down two different branches. Between them, the two matches reconstruct nearly the whole of Derrick's paternal chromosome 18.

One line, read at two depths Inferred

Four of those people are first cousins and their children to the holder of the big tree — 480 to 801 cM with her. They are one tight family, and Derrick stands at second-cousin distance from all of them.

The closest match inverts the ratio. She is 297.5 cM to Derrick and only 60–82 cM to every member of that core. She is not part of it — she is nearer to Derrick than they are. That is not two families. It is one line, read at two depths:

• The closest match's common ancestors with Derrick are his own grandparents. She was born in 1995, two generations below him, and MyHeritage reads her as a first cousin's granddaughter.
• The big-tree holder's are one generation further back — his great-grandparents. Second cousin, 68%.
• Which predicts that those two should be third cousins to each other. They are, at 82.1 cM. The structure is consistent from three directions at once, and that is the strongest thing about it.

Two surnames, at their two depths The short list

At grandparent depth: Halsey. The closest match's own pedigree is Halsey · Halsey · Parr · Parr · Fenton — every one of them living, and named nowhere here. Her match card carries the line that matters: “Ancestral places common to derrick luwinski and [her] include South Africa.”

At great-grandparent depth: Brown, Castle and Webb — documented four generations up in a tree of 10,715 people, and all of these people are dead, so the archive can name them:

Second cousins have parents who were first cousins. So if that reading holds, Derrick's biological father was a first cousin of Geoffrey David Brown or of Hazel Webb — a man of that generation, carrying on the other evidence the surname Halsey, and in Johannesburg in 1948. And Derrick's own great-grandparents are one of four couples: Brown–Brister, Castle–Wallis, Webb–Hayden, or the unrecorded couple behind that Unknown grandfather.

That last one is worth staring at. In a documented tree of 10,715 people, one grandfather is recorded as “Unknown” — in exactly the generation, and exactly the position, where an undocumented connection would sit. Set aside the following day — see below.

This is a structure, not a name, and it is labelled Inferred. What it does is turn an open question into a short list: four couples, one surname, one city, one decade.

Halved again, and the “Unknown” grandfather drops out 15 September 2026

The short list ran to four great-grandparent couples, and the archive made a point of the fourth — a grandfather recorded only as Unknown in a tree of ten thousand people. That was the wrong one to stare at, and one more look at the match pages says so.

The two people who are first cousins to the big-tree holder — 801 cM and 714 cM with her, and Derrick's first and third closest British matches at 333.9 and 165.9 cM — both list Brown among their ancestral surnames. One has Brown, Harrison; the other has Arrow, Brown, Noye.

First cousins share one grandparent couple. If both of hers carry Brown, they are on her father's side — descended from Walter George Brown and Agnes Kate Castle. And if Derrick is a second cousin to all three of them, then his own great-grandparents are the parents of one of that couple:

So Derrick's biological grandparent was a sibling of Walter George Brown or of Agnes Kate Castle, and his biological father was that sibling's son — a man born around 1910 to 1928 who was in Johannesburg in 1948, carrying on the other evidence the surname Halsey.

Held as Inferred, and here are its weaknesses. Brown is among the commonest surnames in England, and both trees are tiny — three people and five. A relationship estimate of “second cousin” carries real width; the same 333.9 cM also reads as half first cousin at 21%. What makes it worth acting on is that two independent first cousins point the same way, and that it is falsifiable: one reply naming a Webb connection would overturn it in a sentence.

First, a confirmation nobody had to argue for

Among the children of Walter George Brown (b. Great Yarmouth 1889, d. Hampshire 1971) is a daughter, Decima Audrey Harrison, 1928–1997. A Brown daughter who married a Harrison. That is where the Harrison match comes from, and it settles by documentation what was inferred yesterday from centimorgans alone: he is on the Brown side.

And then the short list itself Inferred

If Derrick is a second cousin to the tree's keeper, his biological grandparent was a sibling of Walter George Brown or of Agnes Kate Castle. Both sets are now named.

Eight people. Derrick's biological father was a child of one of them, born roughly 1910 to 1928, and in Johannesburg in 1948. The family is Norfolk — Norwich, Great Yarmouth, Caister-on-Sea, and Alfred John Brown was born at a hamlet called California on the Norfolk coast.

Superseded on 15 September. Two things above are wrong. The Castles are Hertfordshire, not Norfolk — only the Browns are Norfolk — and the census puts Derrick's father a generation higher than “a child of one of them”. The four Brown siblings are no longer part of his descent at all. What replaced this →

Which makes one thing suddenly obvious The hypothesis to test

Three of those eight are daughters — Alice Brown, Ada Castle, Martha M. Castle. A daughter's sons do not carry her maiden name. They carry her husband's.

And the surname sitting on Derrick's single closest match, whose shared ancestral place with him is South Africa, is Halsey.

If Alice Brown, Ada Castle or Martha Castle married a Halsey, then her sons were Halseys, born in exactly the right years — and one of them was Derrick's biological father.

It also puts Mervin Halsey, the grandfather the closest match named, exactly where he needs to be: a brother of Derrick's father, another son of that same marriage.

This is checkable without anybody's permission — so it was checked, the same afternoon, in the England and Wales marriage index. The entry is not there. See below.

Tested the same afternoon, and it fails Negative

The Halsey hypothesis was published and then put to the England and Wales marriage index within the hour. It does not survive.

No daughter of these two families married a Halsey in England or Wales. The neat join between the tree on one side and the surname on the other is not in the index, and the archive says so rather than leaving a tidy guess standing.

What survives, and what it means. The eight names came from the tree, not from the hypothesis, and they stand. So does something the tree shows plainly: Alice Brown, Ada Castle and Martha M. Castle have no spouse and no children recorded at all — only parents and siblings. They are genuinely untraced, which is exactly where an unrecorded branch would sit. That is not evidence for the hypothesis; it is the absence of evidence against it.

Three ways it could still be true, and one way it could be wrong from the start. The marriage may have happened in South Africa, outside the English index entirely. The Halsey name may enter a generation lower. Or — and this is the assumption worth naming — Halsey is simply the closest match's father's surname. Her link to Derrick runs through one of her four grandparents, and it could as easily be the Parr side, or her grandmother Cynthia Weir. This archive picked Halsey because it was the name on the card. Open

The grandparents she named a year ago, found

In June 2025 the closest match wrote that her paternal grandparents were “Mervin and Cynthia Halsey — her maiden name was Weir … Cynthia's middle name was Yvonne.” Every particular of that checks out, down to the middle name; the register spells the maiden name Wear rather than Weir.

And the Johannesburg cemetery records carry them both to the end: Mervin Richard Halsey, born 15 June 1930, died 30 May 2005, buried in Johannesburg — indexed there under the given name Kevin, which is the same man and the same middle name and year, mis-read. Cynthia Yvonne Elizabeth Halsey, born 1932, died 4 April 2000, buried at Brixton, Johannesburg.

A supporting negative: there is no Mervin Halsey in the England and Wales birth index for 1900–1940. He was not an Englishman who emigrated. He was South African.

Why his parents are now the whole question Inferred

Mervin was born in 1930, a generation ahead of Derrick. MyHeritage reads the closest match as Derrick's first cousin's granddaughter, and she is Mervin's granddaughter — which puts Mervin himself as Derrick's first cousin.

If that holds, Mervin Richard Halsey's parent was a brother or sister of Derrick's biological father.

One generation, one document. Three ways to get it, in order of likelihood:

• The 1952 register itself, image 2149. The 1956 form has columns for the parents of both parties; the 1948 form has none. 1952 falls between them, and the frame is already located.
• His estate. He died in May 2005, so there should be a J294 naming his father and mother. It is not in the gazette corpus under that spelling — but the Master of the High Court can be asked.
• His birth, South Africa, about 1930.

And the question already put to her this morning — who were Mervin Halsey's parents? — turns out to have been exactly the right one, asked before any of this was known.

Two words in a column nobody was looking at

Derrick's cluster is English. Mervin was born in the Cape, and there is no Hertfordshire, Norfolk or anywhere-else-English in him. His wife was the one born in England — and the match descends from both of them equally. The archive had simply picked the man's surname because it was the one printed on the card.

Three things that were wrong on this page until today Corrected

• The Castles were never in Norfolk. This page said “Norwich and Caister-on-Sea”. That is the Brown side. The Castles are Baldock and Norton, Hertfordshire, and Caroline came from Weston, four miles away.
• Caroline Wallis is Caroline Walls — her widowed father Joseph Walls, born at Weston in 1827, is living in the house in 1911.
• The list of eight was half wrong. Brown enters this family only as the man Agnes Kate Castle married. The four Brown siblings drop out of Derrick's descent entirely.

And the arithmetic changes which generation he sits in Inferred

Two of Derrick's closest matches now descend from one couple, through two different daughters:

Five centimorgans apart, down two separate branches. That symmetry is the whole argument: Derrick is not hanging off one twig of this family, he is equidistant from two — which puts him inside the Baldock household rather than beside it.

And it moves him up a generation. If Derrick's biological grandparent were a Castle sibling, the closest match would be a first cousin three times removed — about 117 cM expected. The reading is 297.5. If his biological father was himself a son of that house, the match is a first cousin twice removed, expected about 212 cM — and that is also, word for word, the relationship MyHeritage printed on the card: first cousin's granddaughter.

Derrick's biological grandparents are, on this reading, named for the first time: George Castle, born Baldock 1863, and Caroline Walls, born Weston 1863, married 1883.

Walked back within the hour. The paragraph above rests on the 292.7 cM match being a grandchild of Agnes Kate Castle. Her tree was then opened and she is a great-grandchild — her father Geoffrey David Brown, born 1926, is Agnes Kate's son. That is one generation further out than the arithmetic above assumed, and it changes the answer from settled to open. The corrected version is immediately below.

Two readings, and the numbers do not cleanly separate them

A fits the centimorgans better. B fits the ages better. MyHeritage's own algorithm returns one of each. And something in the readings is odd on either account: the two great-grandchildren average 313 cM and the great-great-grandchild reads 297.5, when a whole generation should roughly halve it. Two matches a generation apart at almost the same number is not what a simple line of descent produces.

So the honest statement is narrower than the one published an hour earlier, and it is this:

Derrick descends from George Castle and Caroline Walls of Baldock. Whether they are his grandparents or his great-grandparents is not settled, and centimorgans alone will not settle it.

Under A his father is George W. Castle b.1885 or Frederick Castle b.1890 — 63 and 58 in 1948. Ernest b. 28 November 1904 is out: the 1939 Register has him at 29 Norton Crescent, Baldock, a butcher (incapacitated), married, with children, which matches the “invalid” of 1911 and does not match a man in Johannesburg nine years later. Under B his father is one of the grandchildren of that house, born roughly 1910 to 1928 — which is the shape the archive had a week ago, before the surname changed.

What became of the Halseys, for the record NAAIRS, 54 documents

They are no longer Derrick's family, but they were chased for a week and the findings should not simply vanish. The South African national archives index returns, under Halsey:

• WLD 12617/1978 — divorce: Mervin Richard Halsey versus Cynthia Yvonne Elizabeth. They separated in 1978, twenty-six years after St Martin's-in-the-Veld.
• MHG 6348/64 — Erral David Halsey, the estate of the 25-year-old who died at Walvis Bay in July 1964, born at Spaarwater, Heidelberg, Transvaal.
• MHG 790/55 — Penrose Thomas Halsey, who married Helen Edith Stevens at Lower Umgeni, Durban, in July 1914.
• And a Kimberley family older than any of them: Walter 1899, William 1917, Sarah 1920.

A negative worth keeping: the South African death-registration form of that period names parents only where the deceased was under five. Erral David Halsey's 1964 form is complete, legible, and names neither.

And the match list itself now answers to the name Swept the same evening

The search box on Derrick’s DNA Matches page takes an ancestral surname and searches all 5,464. In August it was given Leibholz and Luwinski and returned zero for both. Tonight:

Stated carefully, because the last time this page got excited about a surname tag it was wrong. The 14 is not proof: the top hit is the Castle descendant already known, and thirteen matches at 11–38 cM is the range where a shared surname is suggestive and nothing more. What it does do is put Castle on the opposite side of the ledger from Leibholz and Luwinski, which have never returned a single person.

A trap walked up to and stepped around Checked, not published

Searching the same list for Wear returned eight, and the 292.7 cM match was top of that list too — which looked, for about a minute, like her tree independently containing the Hitchin marriage. It does not. Opening her tree and searching it shows the “Wear” in it is Weare: Henry Weare born 1591, Grace Clarke born 1611.

This is precisely the error this archive published a lesson about in the Figueiredo case — believing a surname tag without opening the tree behind it. The lesson held, one day later, on a finding it would have been very convenient to believe. Open the match before believing the label.

The lesson, which is the same lesson as last time

A week went into Halsey because it was the surname on the card. It was the wrong half of a married couple. The archive had even written down the objection — “Halsey is simply the closest match's father's surname … her link to Derrick could as easily be her grandmother” — and then carried on down the man's line anyway.

Write the objection down, then act on it. Two columns on a register settled in one glance what a week of surname-chasing could not.

“Kurt was twelve before his parents married. What if Jacob wasn't his father — could Kurt still be Derrick's?” Asked 15 September 2026

It is the best objection anyone has put to this page, because it attacks the right joint. Almost everything here assumes Kurt was Jacob's son. He was born on 11 May 1912 to an unmarried Auguste Luwinski, carried her surname, and his parents did not marry until 5 January 1924 — twelve years later. Jacob's paternity of Kurt was never documented at the birth. So: if Jacob were not Kurt's biological father, Kurt would carry no Ashkenazi ancestry, his Y-chromosome would be some other man's, and both of this page's main arguments would collapse.

It fails, and it fails on Auguste rather than on Jacob. Whoever fathered Kurt, Auguste was still his mother — that is the one thing the 1912 entry does record, and it is why he bore her name. So if Kurt were Derrick's father, Auguste would be Derrick's grandmother, and roughly a quarter of Derrick would be her: East Prussian, from Sauerbaum and Allenstein.

There is no room for a German grandmother. Every non-Portuguese percentage points at the Atlantic and the North Sea — English, French, Danish, Breton, Dutch — some 38% of him, against 1.4% Germanic. MyHeritage even names his additional genetic groups as “Southeastern and Eastern England” and “England”.

So the objection does not rescue Kurt. It would have had to survive two independent tests and it only addresses one: rewriting Kurt's father leaves Kurt's mother exactly where she was, and Auguste is not in Derrick's DNA either.

But the question underneath it is a real one, and it is already in the post Open

Was Jacob Leibholz actually Kurt's biological father? That is a separate question from Derrick's paternity, and this archive cannot answer it from DNA — there is no sample from Kurt and none from any Leibholz. But the paper is thinner than the family tree suggests, and one detail is genuinely odd.

Under German law a child born to an unmarried mother took her surname, and Legitimation durch nachfolgende Ehe — legitimation by the parents' subsequent marriage — would ordinarily have made him a Leibholz in 1924. He stayed a Luwinski, to his death in 1968, and registered his own son under that name. Meanwhile his brother Siegfried, born in August 1925 after the marriage, was a Leibholz from the start.

That asymmetry has an innocent explanation — a family that simply never bothered to change a grown boy's name — and a less innocent one. The archive does not know which, and the 1912 birth entry is the document that decides it: a marginal note of Vaterschaftsanerkennung or legitimation, or the absence of one.

It was asked for on 15 September, as the third question in the letter to the Landesarchiv Berlin — before this objection was raised, and for the same reason. If the margin is blank, then Kurt's descent from Jacob rests on nothing but family memory, and this archive will say so.

Every one of them had been written to in June 2025, and three answered

Opening MyHeritage's message window to send a carefully drafted first approach revealed that the matches had all been contacted fifteen months earlier, with one template — and that three of them had replied with names. Nothing in this archive had used any of it. It was found by accident, and it is the worst process failure of the project.

Two things follow at once. The non-paternity was already disclosed to these people in 2025, so the delicacy being written into fresh drafts was, to that extent, beside the point. And the original template asked the wrong question — it asked each of them to work out how they were related and to share a tree, which is labour, rather than telling them something they could react to.

What the three said

The second cousin at 333.9 cM, 18 June 2025 — and he offered everything. “You are very welcome to all the information I have — do you have access to Ancestry? Or I could draw it out. It seems likely Derek and I are related through Great Grandparents … My Paternal Great Grandparents are Harrison / Randall and Crisp and Bray.” He was never answered. It also explains why his MyHeritage tree holds three people: his real tree is on Ancestry. And because his paternal great-grandparents are Harrison, Randall, Crisp and Bray, the Brown in his surname list must be maternal — which is exactly what the Brown–Castle reading requires.

And one remark that does not fit. He checked Salkow, de Witt, Luwinski and Rocha against his own matches, and reported that “Rocha was the only name which appeared.” Rocha is Ivone's side — the maternal, Portuguese one. Either he has an unrelated Portuguese connection, or the tidy split of this archive's two clusters is wrong somewhere. It is the one loose thread in the whole DNA picture, and it should be put to him directly. Open

The closest match of all, 17 June 2025 — and she named four grandparents. Her maternal grandparents were John and Elsie Parr; her paternal grandparents Mervin and Cynthia Halsey, Cynthia born Weir, her mother possibly Mord. Since her common ancestors with Derrick are his own grandparents, one of those couples ought to be the join — most plausibly the Halseys. Four new surnames to work: Halsey, Parr, Weir, Mord.

And the sentence worth staring at, from the match at 165.9 cM, also 17 June 2025: his great-grandfather was “Walley Brown, who was married twice (possibly at the same time)” — and this was on his mother's side. A Brown great-grandfather, maternal, married twice and perhaps bigamously, is precisely the shape of thing that leaves a branch nobody has traced. And Walley may well be Walter — the big tree's grandfather is Walter George Brown, 1889–1971. He added that his sister keeps the family tree and he would pass the message on. Nobody followed up with her either.

What it changes Method

• No cold letters. Everyone in the British cluster already has an open thread. The follow-up sent today went into the existing one, because the drafted version opened “I hope you don't mind a message out of the blue” — which would have been false.
• Answer the man who offered his tree, first. Fifteen months late is better than never, and the offer may still stand.
• Ask for the sister who keeps the other family's tree.
• Put the Rocha question directly. It is the only fact on the table that the two-cluster model cannot absorb.
• The drafted letter to the closest match is obsolete — she has already answered the question it asks.

Read the inbox before writing to it. A day went into composing careful first approaches to people who had already been approached, three of whom had already replied with names.

R-S11477 — R1b, and specifically the North Sea branch

MyHeritage's own page puts it plainly: “R-S11477 is a human paternal lineage nested within the broader R-Z381 haplogroup. Every man who carries it descends from a single ancestor who lived around 200 BCE.” The haplogroup-family badge on the same page reads R1b / Z381, and the node above it on the time tree is R-FGC13328, about 600 BCE.

The chain is R1b → M269 → P311 → U106 → Z381 → FGC13328 → S11477, and the branch that matters is U106. U106 is the North Sea, Germanic branch of R1b: it peaks in the Netherlands at about 37%, and runs at roughly 21% in Germany and Austria and 18% in England and Denmark.

Ashkenazi paternal lines do not look like this. Haplogroup J alone accounts for about 38% of the Ashkenazi paternal gene pool; the characteristic lineages are J1, J2, E1b1b, R1a and G. R1b does occur among Ashkenazi men — but the literature describes R1b-M269 there as repeated punctuated introgression of European Y chromosomes, and the two Ashkenazi R1b clusters that are identifiably Near Eastern belong to R1b-Z2103. A different branch of R1b entirely. Not U106.

What it proves — and what it does not Read this before quoting it

This is not a comparison with Jacob Leibholz's Y-chromosome. The archive does not have Jacob's, and it almost certainly never will, because his male line is exhausted:

So the Y-DNA works by character, not by comparison. It says that Derrick's unbroken father-to-father line belongs to the branch of R1b that peaks in the Netherlands and England, and not to any lineage characteristic of Ashkenazi Jewish paternal descent.

On its own that would not be decisive. A Jewish family can carry a European Y-chromosome — that is exactly what “European introgression” means, and it is why nobody should argue from a haplogroup alone.

But it is not on its own. It is the second independent system to return the same answer. The autosomal estimate says 0.0% Ashkenazi where a quarter is required. The Y-chromosome says the paternal line is North Sea R1b. Different molecules, different inheritance, no contradiction between them, and no evidence anywhere pointing the other way.

Leibholz: nothing. Luwinski: nothing. Exhaustive

Not one of the 5,464 people who share measurable DNA with Derrick carries either name or lists it among their ancestors. This page has said from the beginning that there is no German or Jewish cluster near the top of the list. That was a statement about six matches opened in full. It is now a completed search.

The Portuguese half of that sweep was overstated, and is withdrawn Self-corrected

For about an hour this page said the same search had found Ivone's family — 27 matches for Figueiredo, 13 for Mota — and called it the best lead on her parentage the archive had ever had. That was written before a single one of those matches was opened. Opening them undoes it.

“Shared ancestral surname” is a string match. On the top Figueiredo match — 29.0 cM, fifth or fourth cousin — the two people MyHeritage is pairing are Ivone Mota Figueiredo, born 1924 at Lourenço Marques, and Águeda Maria de Figueiredo, the match's direct ancestor six generations back, born before 12 April 1713. Two centuries and an ocean apart, joined on a string, in a country where Figueiredo is one of the commonest names there is. The shared place is no better: it resolves to “Portugal”, and beside the match's own parish the panel reads “No ancestors in derrick's tree.”

And the Mota matches share no surname with him at all. MyHeritage says so on the 50.1 cM match in plain words. The reason is in Derrick's own indexed surname list — Figueiredo, Leibholz, Luwinski, Schmul, Thimm — which does not contain Mota, because the source tree carries it as a middle name. The thirteen hits were other families' Motas.

The archive already held much better Portuguese matches, worked weeks ago and still on Ivone's page: 108.7 cM at second cousin's son, and 133.2 cM. A 29 cM surname coincidence was never going to beat them. The lesson is cheap and worth keeping: open the match before believing the label.

What the sweep did establish Documented

The two zeroes stand, and they are stronger than they looked. MyHeritage indexes Leibholz and Luwinski as two of Derrick's own five ancestral surnames. So the search was not firing blanks at terms the system had never heard of — it had real, indexed names to match, and across 5,464 people it returned nothing for either.

And there is no computed path to anybody. Filtering his matches for Has Theory of Family Relativity returns “There are no DNA Matches that fit your criteria.” MyHeritage has built no relationship path to a single one of the 5,464. Whatever is found here will be found by hand. Negative, and clean

One loose thread, recorded as loose. The two Portuguese matches that were opened both trace to the Viseu district — Treixedo in Santa Comba Dão, and Tondela and Castro Daire, some 45 km apart along the Dão. Worth noting; not worth believing. Both are distant, one has no documented link to Ivone at all, and the closest Portuguese match by a wide margin records no place more specific than “Portugal”. If Viseu were the family's district, the strongest match ought to show it. Open

Yes — but not from this result, and the reason is arithmetic Tested

FamilyTreeDNA's Discover pages are public, and they list the projects whose members carry R-S11477: Ballew (16 members), Stafford (8), Blakely (8), Byrd (5), York (4), plus a Norman England group and a German-language group. Real surnames, English and Anglo-American, on Derrick's own paternal branch.

They cannot name his father, because surnames are about 800 years old and this branch is about 2,200. R-S11477's common ancestor lived around 200 BCE. Every Ballew and Stafford on it is a cousin at roughly ninety generations, descended from a man who lived before any of those names existed.

That is the theory. It was then tested against Derrick's own match list:

Every one lands between 10 and 28 cM, at the noise floor, and not one is near the close British cluster at 297–334 cM. The prediction was that these surnames would be genealogically meaningless. The match list agrees.

What would work: a Big Y-700, which would place Derrick on one of the 42 branches below R-S11477 — terminal branches in a well-tested lineage are often only three to six centuries old, and at that depth a shared branch usually does mean a shared surname. It would also open FamilyTreeDNA's Y-DNA match list, which is the literal answer to the question and which MyHeritage does not provide at all: a list of men sharing the paternal line, each with their earliest known ancestor's name, year and birthplace.

But the Y is not the best tool available here, and it is worth saying so. The Halsey match is Derrick's first cousin's daughter at 297.5 cM — which means their common ancestors are Derrick's biological grandparents. The surname being looked for is that grandfather's, and it is in her family tree, not in anybody's chromosome. The Harrison match is a second cousin at 333.9 cM, in the United Kingdom. Two messages could produce a name; a Big Y produces a branch number and a probability. Both are worth doing, in that order.

The label does not change, and that is the point Inferred

The method page has said since this archive was built that the paternity finding stays Inferred until a Y-DNA result moves it. The result has been run. It did not overturn the finding — it corroborated it from an independent direction — and there is no further test available, because Jacob's male line has ended.

So the tag stays Inferred. There is still no document and still no direct comparison, and a finding does not become Documented because it survived a test. What has changed is that the test nominated to break it was run, and it held. The archive can now say so without hedging.

Two things would sharpen it further. Big Y-700 — MyHeritage calls its own result a low-resolution estimate; a full sequence would pinpoint the terminal branch and place Derrick in a surname project, and the nearest surname in the British cluster is Halsey. And one message: if any of the Halsey, Harrison or Browne matches is a man descending father-to-father from that family, his Y is directly comparable to Derrick's, and that costs nothing at all.