The 50-year-old grew up with two sisters and insists she never saw male genitalia until her first sexual experience.
"I had never seen a penis until it was at attention and coming at me," she tells her actor friend Justin Long in the latest episode of his podcast, "Life is Short". "Now I have three little boys and I'm, like, 'What the...!' It's an entirely different equipment change."
She also shares that she was unprepared for some aspects of being a boy-mum.
"I have forbidden pulling on each other's penises in the bathtub," she adds, while joking, "I don't know where it (penis) goes, I only had sisters."
But Julie admits her sons are now doing better at keeping their hands to themselves, "They did it (grabbed each other) when they were littler, but now they are 11 and 13. As recently as, like, three years ago a bathtub was a free for all."
And when Justin wonders if her parents ever walked around the house naked when she was growing up, she explains, "Occasionally, but my parents are golf-playing Republicans. These are not the people (who walk around naked)."