Little Sean Preston Federline has a new favorite word, and it “ain’t” Mama!

In a new interview with Rolling Stone Magazine, Britney Spears accuses ex-husband Kevin Federline of teaching the couple’s 3-year-old son, Sean Preston, the F-word.

“Every time they come to visit me, I think about how they’re such special people,” Brit tells Rolling Stone.

“[But they] are starting to learn words like ‘stupid’ and Preston says the F-word now sometimes!”

“He doesn’t get it from us. He must get it from his daddy. I say it, but not around my kids,” she says.