They’re the Hitlers next door.

Some of Adolf Hitler’s last surviving relatives have been living under-the-radar on Long Island for decades, according to a new report.

Hitler’s great nephews Alexander, Louis and Brian Stuart-Houston — the only living descendants of the dictator’s paternal side — live quiet lives in the New York suburbs and fly American flags in their yard, according to Germany’s Bild newspaper, which came knocking at their doors recently.

The three men are the sons of Hitler’s nephew, William Patrick Hitler, who was born in the UK to the Fuhrer’s half-brother, Alois Hitler Jr.

Alois, who left home at 14 and wound up working as a waiter in Dublin, split when “Willy” Hitler was young, according to the New Yorker.

But Willy wound up visiting his estranged dad in Germany in 1929, where he attended a Nuremberg Rally. He then returned to the UK and began giving interviews to the press as Hitler’s “English nephew” — until he was summoned to Berlin to face a furious Fuhrer, the magazine reports.

“What did you tell the newspaper? Who gave you permission to appoint yourself an authority on my private affairs?” he fumed, according to Willy’s mom, Brigid.

“No one must drag my private affairs into the newspapers. I have never said one word they can use. And now there is a ‘nephew’ to tell them all the miserable little details they want to know.”

Willy later traveled to New York, where he continued to give lectures on his infamous family, and eventually registered for military service — joining the US Navy to fight in World War II

After the war, he moved to Patchogue with his German wife and changed the family’s name — first to Hiller and then Stuart-Houston, according to Bild.

He died in 1987 at the age of 76, and his now middle-aged sons have resolutely refused to speak with the media when reporters have come knocking over the years — but Alexander finally broke his silence when Bild showed up recently asking for his opinion on German politics.

The 60-something revealed that he likes German Chancellor Angela Merkel and would vote for her if he could.

“I like her. She’s good. She seems to be an intelligent and smart person,” said Alexander, whose middle name is “Adolf,” according to Bild.

But although he and his brothers are all staunch Republicans, Alexander said he doesn’t care for the current president.

“The last person I would say I admire is Donald Trump. He is definitely not one of my favorites,” he told the newspaper.

“Some things that Trump says, are all right. Most of them are –” he added, trailing off, when asked what he doesn’t like about Trump. “It’s the way he does it that annoys me. And I just don’t like liars.”

Brian and Louis, who live together nearby, wouldn’t talk to the reporter. One of their neighbors said she knew their family history, but said they’re “excellent people,”

“You can’t be blamed for your relatives,” she told the paper.

This story originally appeared in the New York Post.