Speaking on Jimmy Kimmel Live, she said: "My mother's like this very elegant, graceful intellectual, but she will sit through a sex scene like nobody's business. She doesn't sweat at all.
"And last week, actually, I watched our Scandal episode with her, and I had like a three-minute crazy sex scene with Scott Foley, and I was like sweating and fidgeting. And, my mother was like, 'Good work. Very good work.'"
Meanwhile, the 39-year-old actress previously admitted she has tried to quit acting "all the time".
She shared: "I try to quit acting all the time! Not necessarily the show, it's not that I would ever walk away from 'Scandal,' but at times I am like, 'Eh, I'm done with this acting thing.' But being able to tell the story brings me back."
And Kerry credits the show's creator Shonda Rhimes for making it easier for her to return to set after her daughter Isabelle was born.
She said: "Well, last season was my first real experience of working with Isabelle. Honestly, it's no joke! It's the real deal.
"Shonda Rhimes is a wonderful role model. One of the greatest things about having her as a boss is that she is a woman who really understands. She's a mother and has four shows, along with three kids."