The Blue Lagoon actress first became aware of her daughter Rowan’s swearing habit while driving in her car, but put the curse down to childhood naivety.
However, Shields was forced to take action after her offspring cursed at her young pal’s mum – and later found out she had learned the expletive from her grandmother.
She tells British chatshow host Graham Norton, “My seven year old was in the car in the back and I was driving and she must have been three (at the time) and she said, ‘F**k, f**k, f**k, I want my window down, f**k.’ And I didn’t say a thing, and I thought I was safe.
“She had a playdate later the same day and the woman (mother) was quite posh and proper and wealthy and the woman comes over to pick up her daughter and they were sitting at the little art table and my daughter looks up and says, ‘What the f**k are you doing here?’ And she used it properly then and she could tell (it was wrong) as the colour drained from my face. And then I found out she learnt it from my mother.”