Wentz and Camper revealed back in February that they were expecting a baby together, but never revealed the gender. Perhaps because they opted to surprise themselves, too!

"What's more exciting than having the pitter-patter of another little gremlin running around?" Wentz told E! News in May while chatting about his growing brood. "Now it will be two-on-two."

He said at the time that he and Camper were thinking of saving the boy-or-girl reveal for the birth—which, according to the rocker's rep, was Wednesday.

Wentz, who just went platinum-blond a few days ago, shared a pic of a very pregnant, very beautiful Camper about four weeks ago, so we suspected that their baby would be arriving relatively soon.