Jean Baptiste Lacroix / WireImage 1 / 7
Jean Baptiste Lacroix / WireImage 1 / 7

By Kat Giantis

Ashlee Simpson and Pete Wentz seem determined to prove they weren't just blowing smoke with their Feb. 9 split announcement, in which they promised to remain "deeply committed and loving parents to our son Bronx, whose happiness and well-being remains our No. 1 priority."

On Monday, the estranged pair put their differences aside to celebrate Valentine's Day with their towheaded 2-year-old tyke, with the trio rendezvousing for lunch at the swanky Beverly Hills Hotel.

The family arrived and left together in the same Lexus SUV, but an insider downplays the reunion speculation triggered by the meet-up.

"They just had a meal together with their son," the source pooh-poohs to People mag. "They're both focused on making this transition as easy as possible for him."

And perhaps for everyone else. Ashlee, 26, and Pete, 31, chose a venue known for its paparazzi presence, so the outing might have been their way of showing they plan to keep things friendly for their tot's sake.

As snappers clicked away, the pocketsize exes kept their heads down and made their way into the hotel, with the pixie-cut and peroxide-topped Simpson holding onto Bronx's hand (see the pics here).

Wentz, who allegedly tried to talk his wife of nearly three years out of filing for divorce, has also visited her, post-breakup, at the Encino, Calif., estate of her parents, where People says she's staying with their son (she's asked for primary physical custody, along with spousal and child support).

Pete presumably remains in the couple's sprawling Beverly Hills home, although at least one tabloid has some thoughts about the current living situation.

In Touch claims that Ashlee is not actually staying with parents Joe and Tina, choosing instead to crash with big sister Jessica and her fiancé, Eric Johnson.

"Leaving Pete was tough for Ashlee and she needed to be with her family," a spy alleges to the tab. "Jessica told her she and Bronx were welcome to stay with them until she was ready to find a place of her own."

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According to the snitch, "There have been a lot of family dinners and lots of praying. Ashlee couldn't have asked for better support."

But while a family confidant confirms to Gossip Cop that Jess is offering Ashlee a shoulder to cry on, she hasn't offered her a guest room.

Besides, having her kid sister and nephew around might put a crimp in Jessica's romantic adventures.

On Monday night, she tweeted, "9 1/2 Weeks :) Happy Valentines Day!" We're assuming that's a reference to the movie in which the once-smoldering, now-moldering Mickey Rourke enjoys sexytimes with Kim Basinger, and not, say, the results of an ultrasound.

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