Let the battle over Bronx begin.
On Tuesday, Pete Wentz submitted legal papers in L.A. (obtained by TMZ) -- asking for joint primary and legal custody of Bronx, his son with estranged wife Ashlee Simpson.
That's not what Simpson, 26, asked for when she filed for divorce from Wentz, 31, last month: the singer-actress sought primary physical custody (and joint legal custody) of their little boy.
Another discrepancy: Wentz requests that each party pay their own legal fees; Ashlee had asked that the Fall Out Boy rocker pay for the both of them.
The young couple wed in May 2008, when Simpson was already three months pregnant with little Bronx, born that fall.
Pals of the pair told Us Weekly that the twosome quickly became overwhelmed by parenthood.
"Ashlee loves Bronx but jumped into marriage and having a baby too quickly," one source told Us in 2009. "They feel they got trapped in a situation they were too young for."
In a statement released after their divorce announcement, Simpson and Wentz said, "We remain friends and deeply committed and loving parents to our son Bronx, whose happiness and well-being remains our number one priority."