Britney Spears and Kevin Federline have arrived at L.A. Superior Court for a hearing concerning the custody of sons Sean Preston, 2, and Jayden James, 1.

Spears arrived in a white Range Rover and entered the court via an underground entrance. Attorney Blair Berk accompanied the singer.

Federline, 30, showed up after Spears. He was driven through the underground entrance in the backseat of a black Range Rover with his lawyer.

Federline has had primary custody of their kids since January, when Spears, 26, was involuntarily hospitalized after she refused to turn over one of the boys to his bodyguard.

As the singer's stability has improved under the conservatorship of her father, she has been granted regular visits with her sons.

The hearing is expected to include a psychiatrist's evaluation of Spears (who has been shooting her second guest spot on CBS' How I Met Your Mother).