Oooh, baby daddy drama! This should be good. According to Us Weekly, Ryan Phillippe’s ex-girlfriend is claiming that she’s got a little Phillippe in the oven. The chick’s name is Alexis Knapp (photo above), and I have no memory of their allegedly “on-again/off-again” relationship, which apparently lasted for several months last year. CB pointed out this story, from last October – apparently Ryan cheated on Alexis during his birthday party in mid September. Yikes. Us Weekly says they broke up for the final time in September – which is probably right. Now Alexis is claiming that she’s already in her second trimester with Ryan’s baby.

Ryan Phillippe might have to prep for round three of Daddy Duty! The actor, 36, who already has two kids with ex-wife Reese Witherspoon, may become a father again — so says his ex, pregnant model-actress Alexis Knapp, who claims she’s carrying his baby.

(Knapp recently stepped out in Hollywood, bearing an unmistakable baby bump.)

“She’s in the second trimester,” a source confirms to UsMagazine.com of Knapp, who next stars in the film Project X (out this Thanksgiving) plus the Miley Cyrus flick So Undercover. (A rep could not be reached for comment.)

First-time mom Knapp dated Phillippe for several months on and off last year before he ended the relationship in September. “She has been telling people he is the father,” explains another source to Us.

“Ryan doesn’t know if he is the dad,” adds the second source of the Lincoln Lawyer actor. “If he is, he will take full responsibility for the child.”

Explains a third insider of Phillippe and Knapp: “He and Alexis were actually together for a while…It was pretty serious.”

“He’s a good guy,” adds the insider. “He loves being a dad and takes being a dad really seriously.”

His kids with Witherspoon, 35, are Ava, 11, and Deacon, 7.

“If this kid is his,” the insider says, “He will do the right thing. He takes his responsibility seriously.”

Phillippe’s current squeeze is Amanda Seyfried — although the duo have been tight-lipped about their romance. “I’m dating,” said Phillippe on Friday’s Ellen DeGeneres Show. “Not nearly as voracious as the magazines like to make out, [but] I am dating.”

[From Us Weekly]

I kind of have sympathy for both Ryan and this woman. On one hand, Ryan cheated on her and the relationship ended abruptly, and I can see not wanting to have an ongoing relationship with the man who screwed around on you. On the other hand, it feels like Ryan is getting blind-sided with this information, and while he’s a douche about women, he seems like a good, loving father, and he seems like the kind of guy who would want a relationship with every child he fathers. We’ll see how this thing plays out.

Photos courtesy of WENN.