Jeff Vespa / WireImage 1 / 6
Jeff Vespa / WireImage 1 / 6

Jeremy Renner is tackling his most challenging -- and most rewarding -- role yet: fatherhood! The two-time Academy Award nominee and his ex-girlfriend, Sonni Pacheco, welcomed a baby girl on Thursday, two sources confirm exclusively to Us Weekly.

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The "Hansel & Gretel: Witch Hunters" actor told Eva Longoria about his baby news at the Golden Globes on Jan. 13, as exclusively reported in the Jan. 28 issue of Us Weekly. Renner, 42, was overheard saying, "'I'm going to fly in when her water breaks,'" two witnesses revealed. "Then Eva said, 'I'm so blown away.'"

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The "Mission: Impossible - Ghost Protocol" star put his ex-girlfriend up in his L.A. home as they awaited the arrival of their firstborn. "They used to date but it wasn't serious," an insider explained, adding that Renner was "being ultra-secretive about it, but she has been going on about her life and not hiding it."

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Says a pal, "Jeremy will make a great dad!"

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