The `Circus` singer and her ex-husband Kevin Federline - who share two sons Sean Preston, seven, and Jayden James, six, - have reportedly paid off their $37,712 income tax debt, which they both owed from 2004 when they first married.

According to gossip website TMZ.com, the former couple - who divorced in 2007 after three years of marriage - have resolved the debt which was filed against them last month by the State of California.

It is unclear whether the 31-year-old singer - who recently completed her first season as a judge on `The X Factor` USA for which she earned $15 million - paid the entire bill herself.

Meanwhile the Federline family are said to be "very concerned" after an infamous hoaxer called Jonathan Lee Riches pretended to be the singer`s ex brother-in-law Christopher Federline and filed court documents in Florida seeking a restraining order against her and claiming he was the "true father" of her son Sean Preston.

A source close to the family told USMagazine.com: "The signatures match so well. The family is not done investigating!"

Britney recently returned from her Christmas vacation with her fiance Jason Trawick in her hometown Kentwood, Louisiana, amid reports they are currently trying to decide whether their relationship has a future.
sections: Celebrities