London - This month, Boris Johnson, the pro-Brexit human juggernaut who is likely to become the next prime minister of Britain, declared that British immigrants should be required to learn English. In some parts of the country, he complained, “English is not spoken by some people as their first language.”

This naturally upset many Britons, including those in Wales who speak Welsh and those in Scotland who speak Gaelic.

It also upset Johnson’s sister, Rachel, in a manner peculiar to the competitive, tight-knit, look-at-me Johnson clan, which holds a place in British life somewhere in the large, amorphous space between the Kennedys and the Kardashians.

Like her youngest brother and her father, both of whom were once implacable opponents of Brexit (and both of whom have since changed positions), Rachel Johnson has had to perform a complicated jujitsu around her big brother’s candidacy. So, for that matter, have many Conservative politicians who were once in the Never-Boris camp but who in recent weeks have come around to something like an “Only Boris” philosophy.

It is perhaps more complicated within the family itself. Whether because of sibling loyalty, or because they have been warned to behave, or because they just want to burnish their personal brands in preparation for Boris’s ascent, the Johnsons appear to be taking the approach that blood is thicker than political conviction.

So Rachel responded to the English-first flap with a tweet that was classic Johnson. It ensured that she was part of the story. It obscured its implicit criticism of her brother’s remarks with an ad hominem jab implying that political disagreements can be reduced to family jokes. And it allowed her to demonstrate how rarefied the Johnsons are, how different from you and me, in this case because of their classical educations and hyper-articulate cleverness.

“We spoke Ancient Greek at home,” she wrote, presumably exaggerating, though Boris has been known to drop the occasional Latin and Greek bon mot at unexpected times. “I genuinely don’t know what he’s on about.”

The presidency of Donald Trump thrust his family into a loud and central position in American public life. The Johnsons are minor celebrities in Britain because of their high profile in London’s concentrated media-political hothouse. If all goes as expected and Boris Johnson becomes prime minister this coming week, this family of overachievers with dueling opinions will have to adjust to a reality in which one member has overachieved his way to the top.

Rachel, 53 - a columnist, novelist, former magazine editor, talk-show talking head and reality TV star who ran (unsuccessfully) for a seat in the European Parliament this spring on a pro-Remain platform - is not the only high-profile relative of Boris.

There is also Stanley, the 78-year-old family patriarch and a lifelong Europhile who now supports Brexit after opposing it; and Jo, 47, a younger brother and Conservative member of Parliament who voted Remain in the Brexit referendum and changed his position later.

Interestingly enough, the family all calls Boris “Al” - short for Alexander, his actual first name. “Boris is like some sort of public construct that is wheeled out” in nonfamily occasions, novelist and political commentator Robert Harris said in an interview.

A third brother, Leo, 51, the only brown-haired person in a family of blinding blondness, is a sustainability expert and BBC radio host who once said that “I love Boris as a brother but I don’t want to talk about his day job.” There are also two half siblings from Stanley’s second marriage.

In private, the Brexit debate has caused all sorts of difficulties for the family.

“There are various tensions going on,” said Sonia Purnell, author of the biography “Just Boris.” “It’s clear that Jo and Rachel are totally pro-Remain and were aghast and dismayed at what their brother did, but they’re perhaps a bit scared of him, particularly Rachel. There’s also the historic feeling that they had to fend for each other as kids, and so they have a pretty unbreakable bond.”

The family’s current public position is that nothing would be better than for Boris to get the job.

“I’m delighted and proud as punch. What father wouldn’t be?” Stanley said in an interview. A writer, broadcaster, campaigner for environmental causes and former Remainer, Stanley has the same shock of white-blond hair, I’m-thinking-wicked-thoughts expression and air of dishevelment as his more famous son.

“I believe Boris is probably the one person capable of sorting out the Brexit mess,” his father said.

Stanley Johnson said he could not speak for Boris’ siblings and their own internal moral calculations. Rachel, known for rarely passing up a chance to voice her opinion, among other things, demurred on this occasion.

“Aieeee!!” she said via text. “I want to help but if I help you, I have to rebuff a million trillion outlets.”

The family’s youngest brother, Jo, the Conservative member of Parliament, said via email that he was “sorry not to be helpful on this occasion.”

But Jo’s own political journey - from anti-Brexit to reluctantly pro-Brexit to full-fledged Boris-ite - has perhaps been more tortuous than most. After his side lost in the Brexit referendum, he joined Prime Minister Theresa May’s Cabinet with the goal of helping to deliver a good Brexit agreement.

Last fall, he resigned, saying that Brexit had been so badly handled that the only way to avert disaster would be to hold a second referendum. In an indirect swipe at his brother, he said the pro-Brexit campaign had offered “a fantasy set of promises” and a “false prospectus.”

“Brexit has divided the country,” he said in his resignation letter. “It has divided political parties. And it has divided families, too.”

But Jo’s effort to lead the movement for a new referendum fizzled. And soon, the family divisions he had written of seemed to fade away. When Boris eventually announced his candidacy for party leader, Jo was by his side.

Recently, the two campaigned together in Kent, where several shoppers at a plant nursery heckled Boris and told him he was “crazy.” (“It’s a shame your brother’s not running,” a passerby said to Boris, speaking of Jo.)

As Rachel wrote in The Mail on Sunday: “If I had a pound for everyone who has said to me since the referendum, ‘Oooh, must be interesting around the Johnson Sunday lunch table,’ I’d be a rich woman.”