Kevin Federline is "extremely worried" about Britney Spears and feels the psychiatric hospital is the best place for her right now, People reports.
Laying low since Britney was hospitalized again Thursday morning, Federline "doesn't want her to get out until she's made progress," the source says. "This is obviously going to help her in the end - later, much later."
"He's worried. He doesn't even know what's going to happen next."
Kevin Federline and Britney Spears married in 2004, then split in 2006.
Unlike the first time Britney Spears was sent to the hospital, and she had them at her home, the kids were with Federline, who has sole custody.
"Kevin wants Britney to get better. He wants her to be in [Sean Preston and Jayden James'] lives. He wants them to have a loving relationship. He wants her to get healthy so she can be the mother they deserve," says a friend.
This is the second trip to a hospital in a month for Spears.
In early January, she was forced into the hospital following a standoff with police involving sons Sean Preston, 2, and Jayden James, 1.
A court commissioner later stripped Spears of visitation rights.
A third source close to K-Fed says that getting medical help for Spears, 26, "has been planned for a long time. Her family is behind this."