The actress and her boyfriend, Jamie Wollam, are "over the moon"

Credit: Kevin Winter/Getty

Meet the Parents actress Teri Polo and her drummer boyfriend, Jamie Wollam, are expecting a child, her rep tells PEOPLE exclusively.

“I’m over the moon! It’s my favorite role, being a mom,” says Polo. “I know we’re expecting a girl and I’m very, very excited.”

Polo, best known for playing Ben Stiller’s fiancée in Parents and Meet the Fockers, is seven months pregnant.

This will be the first child for Polo, 38, and Wollam together. They also each have a son from previous marriages: Polo has Griffin, 5, and Wollam has Carter, 9.

This pregnancy has been “easier physically” than the last one, Polo tells PEOPLE. “I vowed from the start [not to eat the first thing in sight] so I’m a lot smaller than I was with the first pregnancy.”

Polo and Wollam met in 2004 on the set of a music video for his former band, Avion. She gave Wollam her phone number, he called her the same night – and they’ve been together since. They live together in a four-bedroom house in Los Angeles with their kids and five dogs.

Up next, the actress stars in the film Two: Thirteen, in which she plays a detective overseeing a serial killer investigation.

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