Phillips revealed the sex of her second child on Sunday while promoting her new film, A Case of You. The baby is a girl whose name has not been announced. She will join her older sister, Birdie, 4.
"I haven't said what I'm having yet, I just realized," Phillips, 33, told the Huffington Post. "We've known for a long time now, I just haven't had any reason to say it, but we're having another girl. ... "We're really excited."
The babies' father is Phillips' screenwriter husband Marc Silverstein.
Phillips joked at the film's premiere in New York that her pregnant body had been "hijacked."
"It's all different [with this second pregnancy], and I guess I wasn't fully prepared for that," Phillips said. "My first pregnancy was sort of easy and carefree, and I thought that this one was going to be the same thing. But it has been just worlds apart. But I'm making it through ... I lost my voice because I have acid reflux. I mean it's disgusting! Your body is just hijacked. It's gross."
Cougar Town aired its fourth season finale on TBS April 9. The sitcom has been picked up for a fifth season that will air next year.