Mark Sullivan / 1 / 16
Mark Sullivan / 1 / 16

Ryan Phillippe has not been listed as the father of former girlfriend Alexis Knapp's new baby on the child's birth certificate, according to reports.

The actor's brief 2010 romance with Knapp was kept quiet until it was reported she was expecting the star's baby, months after they split.

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Phillippe stood by the model's bedside when she gave birth to little Kai in Los Angeles on July 1, 2011, but according to the child's birth certificate, obtained by, the actor has not been legally named as a parent. The space was simply left blank.

The newborn's full name was listed as Kailani Merizalde Phillippe Knapp.

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The "Crash" star, who recently split from actress Amanda Seyfried, has a daughter and a son with ex-wife Reese Witherspoon.

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