Friends Guessing a Son for Pete and Ashlee

By Jessica Herndon

09/08/2008 at 04:00 PM EDT

Is there another Fall Out Boy on the way?

Pete Wentz, 29, and wife Ashlee Simpson-Wentz, 23, aren't saying, but pals are guessing the couple are expecting a son – with a lot of spoiling to follow.

"His sneaker collection is going to be ridiculous," Wentz's friend, Gym Class Heroes frontman Travis McCoy, told PEOPLE on Sunday at MTV's Video Music Awards.

And, adds McCoy: "I get to be uncle Travee!"

Ryan Ross of Panic! At the Disco seconded the male prediction.

"I think it's a baby boy," said Ross. "[Pete] will probably teach his kid to play terrible pranks on us. But not if we teach him first!"

So far, the guessing game is just that – guessing. But friends know one thing for sure: impending fatherhood has tamed the Fall Out Boy bassist.

"I've seen a change it that dude," McCoy says. "We were wild kids. We grew up on the road. I was just at his place yesterday and he's getting his grown man on to the fullest. It's a beautiful thing to see."

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