Celebrity Gossip's

Britney Spears' ex Kevin Federline was spotted at a nightclub in Las Vegas over the weekend. K-Fed, who's been staying under the radar recently, finally came out of his hidey-hole to party in the city of secrets while his children stayed at home with a nanny.

K-Fed left his Mirage hotel room around midnight and partied at club Revolution until 3 in the morning, according to a published report.

An insider claims, "He was with his brother Chris and Jason (WeeMan) Acuna from 'Jackass.'"

Meanwhile, Britney Spears wants K-Fed back. Brit, who reportedly tried to kill herself in rehab last week, has been trying to repair her relationship with estranged husband.

A source close to the Promises Rehab told the News of the World, "Britney has realized what a rock Kevin has been to her, and how out of control she has acted recently. She has been talking to Kevin every night for hours on the phone, telling him she still loves him."

"She just wants to be with him again, and thinks having another baby will seal their marriage. Britney seems much happier and has calmed down a lot. She's a completely different Britney from the beginning of the week."