Michael Rozman/The Ellen DeGeneres Show

Jennifer Garner has been mum about her third pregnancy, but she finally opened up about all the good ... and bad!

The Odd Life of Timothy Green star taped a segment for next Tuesday's episode of The Ellen DeGeneres Show, and she admitted that the first trimester was yucky with "all day sickness." But everything's been smooth sailing since ... except for trying to get time alone in the bathroom, that is. Jen told Ellen:

    "The other day I had on a dress and my daughter [Violet] is in there with me, and all of the sudden she went, 'Oh Mom, we have to have a talk.' ... And I said, 'What is going on?' She said, 'Mom, your bottom has gotten so big that your panties don’t give begin to cover it.' I said, 'It’s called a thong you wear it when you’re a grown up.' She was like, 'Uh, that is so gross.'"

Garner's two little girls with hubby Ben Affleck, Violet and Seraphina, also have some interesting ideas about their soon-to-be sibling. "They have a lot of opinions, mostly about names," Jen explained. "They don’t really care about the gender as much as long as we name it what they it to be named ... Ralphie, Frankie, Minnie Mouse, Daisy Duck. Yeah, Rosemarie."

Daisy Duck Affleck? Sounds good to us!