There might not be much buzz about K-Fed's new rap album, but as one half of the highest profile divorce around he sure can cause quite a stir. After his wife, Britney Spears, filed for divorce Nov. 7, Federline, like Spears, announced he wants sole custody, with visitation for the other parent, of the couple's two sons, Sean Preston, 1, and Jayden James, 2 months. "He's interested in having as much time as he's allowed with the kids," says a rep for K-Fed's lawyer Mark Vincent Kaplan. His custody request "could throw a monkey wrench in the divorce," says L.A. lawyer and family law specialist Lynn Soodik. "It could get messy."

In her corner, Spears has powerhouse L.A. lawyer Laura Wasser, 38, who handled Nick Lachey's divorce. A source says Wasser is known for "trying to settle her cases out of the public eye. She looks out for her clients' interests without being unnecessarily aggressive." But another source notes that Kaplan, 59, can be a pit bull, a tactic that could help Federline score a bigger divorce settlement. England's Daily Mail reported that the prenup between Federline, 28, and Spears, 24, awards him only half of their $9.9 million Malibu home and a one-time payment of about $300,000 for spousal support—a fraction of Spears' fortune, which TIME magazine estimated at $150 million. (Neither Spears nor Federline had any comment about the Mail report.) California law also entitles Federline, by far the lesser earner of the two, to receive monthly child support payments. Of course, Federline could contest the prenup, which would make the divorce a full-fledged battle for both cash and custody. A more likely scenario, though, is that the couple will agree to joint custody, and that Spears "will keep raising the settlement offer until Kevin takes it and resolves the divorce quietly," says a legal source.

While Fed-Ex, as he's now known, was pushing on with his rap tour (several shows were canceled due to dismal ticket sales) last week, Spears swooped in to see her family in Kentwood, La., with both kids in tow. "She's happy, and she's doing just fine and the babies are gorgeous," says longtime family friend Nyla Price, 55. Spears is also done with her maternity leave—and back in the recording studio. "She's happy as hell!" says songwriter/producer Sean Garrett, who is working with her on her next album. "I know it sounds crazy, but she's in very good spirits. She's ready to get out there and do what she does best."

For up-to-the-minute coverage of the breakup, go to PEOPLE.COM/BRITNEY