Britney Spears blames her ex-husband Kevin Federline for teaching their three-year-old son to swear.
The pop superstar currently shares custody of Sean Preston, three, and Jayden James, two, with Federline following their split in 2006.
But, despite being full of praise for her former spouse's parenting skills, Spears is not impressed to hear her sons mimicking his explicit language.
She tells Rolling Stone magazine, "(The boys) 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."