The twins will be born in the fall to a "gestational carrier"

By Alicia Dennis
Updated June 10, 2007 10:00 AM

Dennis Quaid and wife Kimberly know what to expect now that they’re expecting: one of each.

“We finally know the sexes of these sweet little children coming into the world – we’ve seen pictures of them,” Quaid told the crowd Saturday at his 5th Annual Dennis Quaid Charity Weekend in Austin. “One of them was a boy and one of them was a girl.”

The twins will be born around Thanksgiving to a “gestational carrier” – a woman who carries another couple’s baby conceived by the parents’ own egg and sperm. The pregnancy was announced last month.

“I’m over the moon,” Quaid told PEOPLE. “We are both so thrilled and excited. This is something we’ve wanted for some time.”

These will be Quaid’s second and third children; he also has a teen-aged son with ex-wife Meg Ryan.