"He likes Bob and he likes guitar – which he calls 'itar,’ so we're going to have a Spongebob party for him," Wentz said.
On the guest list? "A bunch of friends," he said. "Like all the guys in Blink  and a couple friends that have kids [are coming over]."
Simpson-Wentz, 25, makes her Broadway debut as Roxie Hart Nov. 30. (She played the role in the London production in 2006.)
Bronx may need a babysitter that night. Asked if he will be attending his wife's debut, Wentz said, "I think I will be."