According to Page Six, Britney Spears desperately wanted to invite her ex-husband, Kevin Federline, to her birthday party on Sunday, but Kevin was busy… you know, watching their children.

Spears wanted to call her ex-husband, Kevin Federline, but had to use Hilton’s cellphone “because she could not find her own,” a source said

Spears invited Federline to join her at the club during the 1 a.m. call.

“She begged him to come out with her,” a source said, “[but] “Kevin reminded her that one of them needed to be a parent and take care of the boys. Then she hung up on him. Kevin said she was drinking.”

I wonder if she couldn’t find her cell, or if she realized there was no way he would answer her calls.

Britney: “Heeeyyy, Kevin, how-r yooouuu?”
K-Fed: “What do you want, Britney? Do you know what time it is?”
Britney: “Aw, c’mon, it’s mah BIRFDAY. Come to mah party! We have cake…”
K-Fed: “Well, if you have cake, then maybe I could—”
Britney: “No wait, check that. The cake’s all gone. But you could have meeee….hee hee.”
K-Fed: (click) (dial tone)