They just can't stay apart?

Although they filed divorce papers last week, Ashlee Simpson-Wentz and Pete Wentz had lunch together on the most romantic day of the year -- along with their son Bronx, 2.

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As documented in photos at X17online, the singer-actress, 26, and the rocker, 31, shared a midday meal on Valentine's Day with their little boy at the Beverly Hills Hotel Polo Lounge; the casually-dressed family of three arrived and departed together in the same car.

No word yet on whether the couple are reconsidering their decision to split. After embarking on a relationship in late 2006, they married in May 2008 and welcomed their son that fall. In last Wednesday's statement following their divorce announcement, they said that Bronx's "happiness and well-being remains our number-one priority."

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The duo encountered major problems just 13 months into their union -- battling it out explosive, often public spats.

"Ashlee loves Bronx but jumped into marriage and having a baby too quickly," one pal told Us Weekly in summer 2009. "They feel they got trapped in a situation they were too young for."

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Read more about the shocking split in the new issue of Us Weekly, out Wednesday.

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