Britney Spears & Tony Romo party together

According to reports, troubled singer Britney Spears hit the town with friend Alli Sims – and Dallas Cowboys quarterback Tony Romo.

According to People.com, Spears, currently battled in a bitter custody battle with former husband K-Fed, dressed in a masquerade ball mask, and Sims, first made a quick stop at the L.A. restaurant Ketchup where Romo was having dinner.

A Source told the publication that: "Spears walked around the restaurant into the lounge where she met up with some people," an observer tells PEOPLE. "She didn't eat or drink …[It] seemed like she was rounding up people to go to [out]. She was very friendly and smiley, in and out."

Another source claims, "Alli was meeting up with Tony and his friends at Ketchup and Britney wanted to come along. Tony and Alli have been good friends. They've known each other for a little over a year. "

Later, the Dallas Cowboys quarterback met up with Sims, Spears and other pals at the Hollywood's Les Deux where they hung out upstairs.

Spears was "sitting with her friends and Tony. Everyone was just hanging out. Brit was upbeat, really seemed fine."

The following night, perhaps in a nod to her friend Romo, a source says "Sims even playfully dressed as a quarterback for Ryan Cabrera's costume party on Saturday night."