Katherine Heigl's mother enjoys her foul mouth.
07/16/2009 - Katherine Heigl - Katherine, 30, said: "The language is wild, but she's heard a lot worse from me. Don't tell her I said this, but she can dish out those raunchy words pretty well herself." © Albert L. Ortega / PR Photos
The 'Ugly Truth' actress said her manager mom, Nancy, won't be shocked by her character's swearing in the movie, as she often uses bad language herself.
Katherine, 30, said: "The language is wild, but she's heard a lot worse from me. Don't tell her I said this, but she can dish out those raunchy words pretty well herself."
The actress also isn't concerned about her mother seeing her sex scenes with screen heartthrob Gerard Butler.
She added: "She's never there when we film that stuff, and it's not just because she doesn't want to worry me.
"You can imagine it would make Gerard Butler pretty uncomfortable if he was in bed with me while my mother was watching. If it didn't, it would be weird and kinky."
Katherine said the film - in which she plays an unlucky in love TV presenter - will reveal the truth about men's attitudes to love and sex.
She continued to Parade magazine: "I know way too much about men and now, thanks to 'The Ugly Truth', the world will too.
"It's no great surprise to me what's going through their brains and it's not about the L-word but the S-word.
"Guys are much more obvious than they think they are. I don't know why all women don't know this, but I think it's because we just don't want to believe that about guys.
"We want males to be better than they really are."
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