Fall Out Boy bassist Pete Wentz and his estranged wife Ashlee Simpson are in a custody battle over their son.

Simpson, filed for divorce from Wentz on Wednesday (February 9), citing irreconcilable differences after two and a half years of marriage. The pair are now in a custody battle over their two-year-old son, Bronx.

Wentz has submitted legal papers asking for joint primary and legal custody of Bronx after Simpson sought primary physical custody, reports Rolling Stone.

Wentz and Simpson married in May 2008 at a private ceremony conducted by Simpson's father, Joe. They had been dating for two years.

(by Holly Frith)