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With two daughters at home, Chris Rock knows a thing or two about parenthood.

At the NYC premiere of What to Expect When You're Expecting Tuesday night, the father to Lola, 9, and Zahra, 7 (with wife of nearly sixteen years, Malaak Compton-Rock) opened up to Us Weekly about his costars' parenting skills.

"[Jennifer Lopez] is a great mom," he told Us, explaining it's easy to tell just from talking to her how much she cares for twins Max and Emme, 3. "We're on the set. We're talking," Rock shared. "You can tell who is into their kids and who's not."

On hearing that Lopez, 42--who is currently dating choreographer Casper Smart, 25--has expressed interest in having more kids, Rock joked he'd be more than willing to help her out with that endeavor. "I know!" he said. "I might get her pregnant."

As for his costars without children?

"Cameron [Diaz] would make an amazing mom," the 47-year-old comedian revealed. "She's just fun. She doesn't take herself too seriously."

This month, Diaz, 39, spoke to Redbook about learning to be more flexible with her life plans.

"I thought I was going to be married and have two children by the time I was 21," the single actress reveals. "I think I felt I had to model my life after my mother's."

As her career picked up, Diaz realized she would need to put having a family on hold--and that it wasn't the end of the world.

"After that I never put another timeline on anything in my life," Diaz tells the mag.