Britney Spears and Kevin Federline
Britney Spears and Kevin Federline were married in 2004. Spears gave birth to her first child, Sean Preston Federline, in 2005 and her second child, Jayden James Federline, was born in 2006. A few months after Jayden’s birth, Spears filed for divorce, which was finalized in 2007. The couple agreed to have joint custody of their children, but when Spears checked into a drug rehabilitation center and had a public meltdown, Federline received full custody of the children in October 2007. Spears, however, refused to give up custody of her sons and appeared at Federline’s home in January 2008. She was committed to a psychiatric ward and her father, Jamie, gained control of her finances. She was released a month later. Since then the pop star has made major life changes and she has regained joint custody of her children. REUTERS/Mario Anzuoni

Britney Spears has dealt with more than her share of bizarre legal allegations over the past few years, but the latest one takes the cake. Chris Federline, the younger brother of Kevin Federline, has reportedly filed a temporary restraining order against Spears in which he claimed to have fathered her oldest son, 7-year-old Sean Preston.

Chris Federline filed the order in a District Court in Tampa, Fla., on Dec. 18, according to Radar Online. Federline claimed in court documents that the "Toxic" singer had harassed and blackmailed him, and even stole his Capital One credit card to go on a shopping spree.

“She is out-of-control and a maniac,” Federline said in the court filings. Federline alleged that Britney, who has an estimated net worth of about $200 million, stole his credit card after stopping by his house to pick up her two sons, Sean Preston and Jayden James, and seeing his wallet lying on the coffee table.

He claimed that after racking up more than $4,500 in charges on the card, Britney threatened to expose their previous affair unless he kept quiet.

"Britney … laughed at me [and] told me my brother Kevin ruined her life. Britney made fun of me and told me I have a small penis," Federline said.She also blackmailed me and told me if I tell the police that she stole my credit card, that she will tell the world I’m the true father of Sean Preston, not Kevin."

"I do confess I slept with Britney, and I am the true father, but the public does not need to know," Federline continued, in the publicly filed document.

The National Enquirer reported that an inside source said that Chris Federline considered the affair "a mistake."

"He says he always felt bad about it and kept it to himself because he didn’t want Alisha, his wife at the time, to find out,” said the source.

While Chris Federline's bombshell allegations are possibly the wildest claims ever made about the "X Factor" host, he is not the first to accuse the singer of being "out of control." In October, Britney's former manager, Sam Lufti, sued her parents, Jamie and Lynne, for libel and breach of contract. In the suit, Lufti claimed that Britney had previously been addicted to amphetamines when she employed him, and that her involuntary committal to a mental ward in 2008 had been a result of drugs.

"My client was made a scapegoat for the drug abuse and erratic behavior of Britney Spears," said Lufti's lawyer, Joseph Schleimer, during the trial. "She liked to use amphetamines—speed or uppers. She liked to take that drug. And most of the things that went wrong were related to that drug."