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Dakota Johnson and Marilyn Monroe Are 'Ninth Cousins, Three Times Removed'

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The Green Room · LifePivo's culture desk

Here Is Why That Is Barely a Family Tie at All

The same week the first images landed of Dakota Johnson made up as Marilyn Monroe — platinum hair, painted lip, unmistakable and slightly uncanny — a genealogy company put out a press release with a headline gift attached: the two women are related. Johnson, it said, is Monroe's ninth cousin three times removed. A researcher's line did the rest of the work. "Discovering that Dakota Johnson and Marilyn Monroe are related turns the casting into a real-life family story," MyHeritage's Naama Lanski was quoted saying, and by the next morning the framing had travelled: an actress playing an icon turns out to be the icon's family.

It is a lovely line for a film about to premiere in Venice. It is also, in the sense most readers will take it, not really true. A ninth cousin three times removed is a genuine entry on a family tree and, at the same time, one of the emptiest relationships the word "cousin" can describe. Here is what the claim is, where it comes from, and why the distance in it is the whole point.

A press release timed to a first look

The peg is a film. Flesh Impact is a short — about seventeen minutes — directed by Maggie Gyllenhaal, made to mark the centenary of Monroe's birth (she was born on 1 June 1926) and set to premiere at the Venice Film Festival in September 2026. It casts two actresses as Monroe: Johnson plays her at the height of her 1950s fame, and Ellen Burstyn plays an older Monroe — a version who, in the film's imagining, lived on past the death that actually came in 1962.

The genealogy claim arrived alongside that first look, not out of it. MyHeritage, a company whose business is exactly this kind of family-tree research, says it traced both women's lines back to Richard and Charity Tydings, English settlers who reached colonial Maryland in the mid-1600s. Monroe, the firm says, descends from the couple's daughter Pretitia; Johnson — and her father, the actor Don Johnson — descend from a younger daughter, Mary. Two sisters, two branches, and roughly four centuries later, an actress cast as the woman at the far end of the other branch.

We are reporting that as MyHeritage's claim, because that is what it is: the company's own research, announced by the company, and carried by outlets that picked up its release. It is plausible and consistent across the accounts. But a family-tree finding announced by a firm that sells family-tree subscriptions, in the same week as a film's marketing, is worth reading as what it is — a good line, professionally timed — before it is repeated as a fact about blood.

Ninth cousins share a couple who died before the country existed

The reason the relationship feels bigger than it is comes down to arithmetic that headlines never carry. Cousin numbers count generations back to a shared ancestor. First cousins share a set of grandparents. Second cousins share great-grandparents. Each step out adds a "great" and a generation, so ninth cousins share a set of eighth-great-grandparents — a common couple about ten generations up the tree. The Tydings pair, reaching Maryland in the 1650s, sit right about there.

"Three times removed" is a second measurement laid on top of the first. "Removed" means the two people are not the same number of generations down from that shared couple; the number counts the gap. Monroe was born in 1926, Johnson in 1989 — the better part of three generations apart — so one of them sits three rungs further down the same ladder than the other. That is all "three times removed" records: not a closeness, but an offset.

Put the two together and you have two people whose most recent common ancestors are a husband and wife who died before the United States existed, with an extra three-generation stagger between them. It is a real path on paper. It is also about as distant as a documented cousinship gets before the trail runs out entirely.

This is the same move a studio press tour makes with a casting rumour, only run through a family tree: a true, narrow fact — two lines cross at a couple in the 1600s — dressed as a larger one. We spent a whole piece separating that kind of confirmed detail from the marketing around it on Spider-Man: Brand New Day, where "the cast confirmed it" and "the trailer implied it" turned out to be very different claims. A genealogy release rewards the same reading.

In DNA terms, that is close to no relation at all

The gap between "related on paper" and "related in any way you can measure" is where this story actually lives, and it is not subtle.

You inherit half your DNA from each parent, and which half is a coin toss at every generation. Trace a line back far enough and the slice of your genome that came from any one distant ancestor keeps getting halved, until it rounds to nothing you could detect. Genealogy testing services have measured where that happens, and it is not far out. Second cousins share about 3 percent of their DNA on average; third cousins less than 1 percent. By the fourth-cousin level, according to the cousin-DNA guides that consumer testing companies publish, roughly half of all such pairs share no detectable DNA at all — and, as one guide puts it, "fifth cousins or more distant relatives often share no detectable genetic material." Past fifth cousins, the chance of sharing any measurable DNA drops below about one in twenty.

Ninth cousins are four full steps beyond that cliff. The honest way to state it is not a precise percentage — nobody can hand you a clean number that far out — but a direction: the expected shared DNA has been halved so many times that, for the overwhelming majority of ninth cousins, there is none left to find. Johnson and Monroe are cousins the way a document says so, not the way a cheek swab would. Nothing in the genealogy claim asserts otherwise, and nothing here should be read to say they carry a shared, detectable inheritance from those Maryland settlers. Almost certainly, they do not.

Why almost everyone is somebody's ninth cousin

The last piece is why "ninth cousin" is not just distant but ordinary. Every generation you go back roughly doubles your number of ancestors — two parents, four grandparents, eight, sixteen — and the same doubling runs forward from any ancestral couple into their descendants. Ten generations of that turns one 17th-century marriage into an enormous fan of living descendants. Everyone with roots in colonial America is sitting somewhere in a great many of those fans at once.

The upshot, which genealogists will tell you without prompting, is that a person has a staggering number of distant cousins — far too many to be special about any single one. Being someone's ninth cousin is closer to a statistical near-certainty among people who share a region and a few centuries than it is to a discovery. Reach into almost any pair of Americans of long colonial descent and you will find a cousinship at roughly this distance if you dig for it. What makes the Monroe–Johnson version a story is not the link. It is that one of the two happens to be playing the other in a film.

That is not a knock on the research — the trees may well be right, and tracing them is real work. It is a note about what the finding can bear. A story built on a distant-cousin link is doing the same thing as a coming-of-age drama built on a director's own childhood memory: taking a true thread and asking it to carry a lot of weight. When the Luton debut Ish drew on its director's real stop-and-search at twelve, the film was careful about the line between what happened and what it made of it. A one-line genealogy claim, written to travel, is not.

What is solid, and what is just a good line

Strip it down and the verified core is small and fine: MyHeritage says its research puts Johnson and Monroe on two branches of a Maryland family that split in the 1600s, ninth cousins three times removed, and Johnson is playing Monroe in a Venice short called Flesh Impact. The film is real, the casting is real, and the cousinship is a documented paper-trail relationship as the company describes it.

What is not established is everything the framing invites you to add: that this is a meaningful family tie, that the two women share anything you could measure, that "real-life family story" means more than a common couple ten generations back. Those are the parts a headline supplies for free, and the parts worth setting down before the sentence "Marilyn Monroe is Dakota Johnson's cousin" hardens into something people believe they know. They are cousins in the way that, if you looked, a great many strangers would turn out to be. The film is the reason to care; the family tree is the marketing.

Sources and verification