Arnold Schwarzenegger, Maria Shriver Divorce: Couple Reunite To Celebrate Arnold's Birthday (VIDEO)

Despite their impending divorce, Maria Shriver and Arnold Schwarzenegger came together on Saturday to celebrate the former governor's 64th birthday. Together with their two sons Patrick, 17, and Christopher, 13, who was recently released from the hospital last week after suffering a collapsed lung and broken bones from a boogey-boarding accident, the pair reportedly shared lunch in Beverly Hills then stopped by Barneys New York for some shopping.

According to an onlooker quoted in "US Weekly," the estranged couple "seemed relaxed," behaving as though it were a "pretty normal" family outing.

Shriver and Schwarzenegger have made an effort to present a united front--particularly when it comes to family matters. Both parents Tweeted their thanks for the public outpouring of support for their injured son after his accident, and were "a constant presence" at his hospital bedside, according to the UK's "Daily Mail."

In what was perhaps another show of solidarity, last week Schwarzenegger amended his original divorce filing--in which he requested that Shriver's bid for spousal support be terminated, and that Shriver pay her own attorney fees--and replaced it with a new document that withdraws both requests.

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