Raul Castro replaced as Cuba's president
Raul Castro replaced as Cuba's president
'Cougar Town' Star Having Baby Girl
PHOTO: Busy Philipps attends the "A Case Of You" World Premiere during the 2013 Tribeca Film Festival, April 21, 2013, in New York City.

Mike Coppola/Getty Images

Busy Phillips' four-year-old daughter is getting a sister.

The "Cougar Town" star, who is expecting her second child with husband Marc Silverstein, revealed to the Huffington Post that she's having another girl.

"We've known for a long time now. I just haven't had any reason to say it, but we're having another girl," Phillips said when asked the gender of her unborn child at Sunday's red carpet premiere of her film "A Case of You."

The baby's big-sister-to-be, Birdie, is "super excited" about the news - at least for now, Phillips said.

WATCH: Busy Phillips Dish on 'Cougar Town'

"She's actually incredibly helpful and she's 4 1/2, so she's really understanding things. When I say, like, 'Mom can't carry you right now because the baby in her tummy is pressing down on her bladder!' She understands what that means and she's cool with it," the 33-year-old actress said.

"But we'll see what happens when the actual baby comes," Phillips added. "I'm planning for that moment, like, 'And when does she go back?' I know that will happen."

Phillips also revealed that her second pregnancy has been more difficult than her first.

"I lost my voice because I have acid reflux. I mean, it's disgusting!" she said.

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