Ryan Phillippe Hangs With Pregnant Ex Alexis Knapp

Dutiful dad-to-be?

On Monday, Ryan Phillippe was photographed in Los Angeles for the very first time with Alexis Knapp, his very pregnant ex-girlfriend. Phillippe and the model-actress, who dated on and off last year, were snapped picking up cold beverages at a Coffee Bean & Tea Leaf before heading into an obstetrician's office. Phillippe, 36, then dropped off the first-time mom-to-be, 21, at her home.

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Back in March, Us Weekly was first to break news that Knapp was expecting -- and had announced to pals that ex Phillippe (they split for good in September 2010) was the father.

The Lincoln Lawyer actor (dad to Ava, 11, and Deacon, 7, with ex-wife Reese Witherpsoon) has  remained mum his ex's talked-about pregnancy. "He doesn't know if he's the father," one insider told Us, adding that he plans to take a paternity test. "If it's his, he'll take responsibility."

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So Undercover star Knapp, meanwhile is "really excited to be a mom," another insider said.

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She has similarly not spoken publicly about her baby-to-be, who is reportedly due soon. "Alexis has maintained her silence and will continue to do so," her rep told Us in March. "She continues to appreciate the love and support of her family and friends."