Eva Mendes Wants Ryan Gosling's Baby!

It might be time for Ryan Gosling to put up or shut up with girlfriend Eva Mendes, as the stunning actress is demanding a little Gosling from the Hollywood hunk.

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"Eva has given Ryan an ultimatum. She told Ryan she wants a baby with him, and that if he isn't prepared to that, they should split up," a source tells Star.

Eva, 38, has told multiple friends she is off the Pill and ready to become a mom.

"Eva's clock is ticking," says the source. "She's been aching to start a family for a few years — and even seriously looked into adoption in the summer of 2010. But now she and Ryan are together, and he's mature beyond his years and great with kids."

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But that doesn't mean Ryan's totally on board himself.

"Ryan loves Eva, but he isn't ready for a baby right now — he's concentrating on his career," the source explains.

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