Julia Roberts, 43: It’s “Bizarre” to Play Mom to Ryan Reynolds, 34, in Film

 Kevin Winter/Getty Images; Steve Granitz/WireImage.com

That's some precocious procreating, pretty woman!

In the family drama Fireflies in the Garden, out this Friday, Julia Roberts plays mother to Ryan Reynolds — despite just a nine-year age difference between the stars.

At Wednesday's L.A. premiere of the film, Roberts, 43, admitted to Us Weekly portraying the mother-son bond with Reynolds, 34, was "bizarre at first, because he's so tall!"

The real-life mother of three added, "But it worked out all right. He's a good boy!"

Although Fireflies (also starring Willem Dafoe, Emily Watson and Hayden Panettiere) was completed and ready for theaters in 2008, distribution issues delayed its release for three years. At the time of filming, Roberts was seven months pregnant with Henry, now 4, her youngest with husband Daniel Moder. (Henry's older siblings are twins Hazel and Finn, nearly 7.)

"[I was] nice and ready to have a baby!" the Pretty Woman actress quipped. Watching the flick now offers a great time capsule of her pregnancy, she told Us. " When I see it now and he is this big boy who can dress himself and do these things, it really is touching to see that."

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