After a closed-door hearing Monday, a judge ordered that, from Wednesday, Kevin Federline gets physical custody of Sean Preston, 2, and Jayden James, 1, "until further order of the court."

L.A. Superior Court Commissioner Scott Gordon didn't outline his reasons in the written ruling, but Spears's attorney, Sorrell Trope, says, "We weren't able to prove compliance with what the judge ordered."

"Specifically," Trope says, "the judge ordered that by 10 a.m. (Monday) morning, both parties show valid California driving licenses. I've been unable to produce evidence of that."