Greg Tidwell / Pacific Coast News 1 / 6
Greg Tidwell / Pacific Coast News 1 / 6

By Kat Giantis

Four years after Reese Witherspoon and Ryan Phillippe called time on their marriage, it looks like both are about to experience major life changes.

As rumors fly that the Oscar-winning actress is preparing to marry talent agent Jim Toth sooner rather than later, the actor is dealing with the fallout from reports that one of his ex-girlfriends, actress-model Alexis Knapp, is pregnant with his child.

First up is Reese, who RadarOnline believes will say "I do" on March 26 at her ritzily rustic weekend retreat in Ojai, Calif.

About 100 or so guests are supposedly attending what's being billed as an "intimate" ceremony filled with candles and flowers in white and pastels.

Toth popped the question late last year after about a year of dating, and Witherspoon, her all-important finger now weighed down with a behemoth $250,000 sparkler, has been spotted shopping in Paris and Los Angeles in preparation for the big day.

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But in between the nuptial planning, Witherspoon has apparently found time to offer a sympathetic ear to Phillippe, with whom she has two look-alike tots, 11-year-old Ava and 7-year-old Deacon.

"Ryan has really confided in Reese about this," a source tells Us Weekly of the baby talk. "Reese has been really supportive. She knows that Ryan is a good dad, and she respects that."

Meanwhile, there's still some question about when -- and how -- Ryan found out he might become a father for the third time (pending DNA tests, natch).

A source asserts to People magazine that he's "known from the very beginning. As soon as [Alexis] found out, she told him. She found out she was pregnant while she was filming 'So Undercover' [with Miley Cyrus]."

But Us paints a less amicable picture of the big reveal, alleging that Knapp, 26, "blindsided" Phillippe, 36, by dropping the daddy news last month at a Hollywood shindig -- a shindig that the actor didn't even attend.

He supposedly heard about the public paternity announcement through the grapevine.

"Alexis hadn't even talked to Ryan before that party," huffs a snitch.

And don't expect Phillippe to do any talking until after he is (or is not) identified as the dad.

"In all likelihood," an insider tells People, "Ryan's not doing or saying anything publicly until there's a paternity test that proves he's the father."

And if he is? "He'll take responsibility," a confidant assures Us.

As for Amanda Seyfried, whose four-month relationship with Phillippe has been dogged by breakup rumors, "This is the last thing [she] needs," a source sighs to In Touch.

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