Teddy Pendergrass II and Joan Pendergrass have produced conflicting wills since the singer died of colon cancer in January.
The son claims a will from May 2009 names him executor and sole beneficiary. The widow claims a later document on which she signed her name as the singer's attorney gives her control.
Teddy Pendergrass II tells The Philadelphia Inquirer that his father left him in charge of the family. Joan Pendergrass' attorney denies a money grab, saying the estate has few assets.
Attorneys for both sides met with a judge last week but failed to reach a compromise.
Teddy Pendergrass is best known as the singer of "If You Don't Know Me By Now" and other hits.