Britney Spears re-entered the Promises Rehabilitation Center on Thursday allegedly upon the threat of losing custody of her two children with Kevin Federline. She returned to the center on Wednesday night around 10:30 p.m., according to British newspaper, the Mirror.

Yesterday reports arose that Federline and his lawyer, Mark Vincent Kaplan had called an emergency custody hearing for his children with Spears. Kaplan's publicist, however, denied the story to Fox News.

Still, one source for the Mirror says

When Britney realized Kevin was going to court, she quit rehab, hid out and then went for an emergency meeting with her own lawyers.

The Mirror claims that later on Federline told Spears

Go back to rehab right now and I won't go to court.

Britney's mother Lynne was present when she returned to Promises to continue her rehab program. A source close to the Spears family told the Mirror

Her mum is desperate with worry and can't sleep at night. She just wants Britney to get well and has told her rehab is the best place for her.

According to the Sun, Lynne told Britney

I want you to get help or I fear you'll end up killing yourself.

Britney's father, Jamie echoed his former wife's concern for their daughter in an interview with Fox News. He said

We've got a sick little girl - we're just trying to take care of her.

Jamie also said that the issues with Britney are "not about what other people think."

Britney appeared to reach her breaking point on Wednesday night when she attempted to find Kevin at his home. One source for the Sun said Britney banged on Kevin's door for 20 minutes, yelling

Let me in, I want to see the kids. Give me my children back.

A witness to the scene told the Mirror

It was heart-breaking seeing her driving around the block, banging on the door and screaming at the intercom. She did this five times and seemed angry and agitated.

Britney took out her anger on one of the photographers that was following her and went after him with an umbrella. The Mirror's source said

She ran at the guy as he flashed her and kept swiping at him with the [umbrella]. It was like a tragi-comedy.

Another onlooker told the Sun

She went crazy. It looked like she was at cracking point.