(Cover) - EN Showbiz - Olivia Wilde believes that Jennifer Garner "should keep breeding".

The 27-year-old actress and Jennifer co-star in upcoming comedy Butter.

Jennifer is currently expecting a child with husband Ben Affleck. The couple already have daughters Violet, 5, and 2-year-old Seraphine, and will add the third addition to their brood sometime this winter.

Although Jennifer and Ben have their hands full already, Olivia believes the couple should have many more children together in the future.

"[Jennifer and Ben] should keep breeding. She makes pretty babies," Olivia told Us Weekly at the Artios Awards in Beverly Hills Monday.

When Jennifer is not spending time with her ever-expanding brood, Olivia welcomes the mother's presence on film sets. Olivia thoroughly enjoyed working with the brunette star.

"She was such an awesome co-star and a wonderful producer," Olivia gushed.

Olivia is hoping to work with more women like Jennifer in the future. Although she enjoys spending time on set with the boys, girl talk would be much appreciated at times.

"I've worked with a lot of the greatest guys in the business, and now I am slowly working with more and more women," Olivia explained. "We don't really get to work together, the girls so much!"

Butter will be released on October 21. (C) Cover Media