Pete Wentz, Girlfriend Meagan Camper Take Bronx, 5, to Big Hero 6 Premiere: See Him All Grown Up!

Bronx Mowgli, Pete Wentz and Meagan Camper
Bronx, Pete Wentz and Meagan Camper attend the Big Hero 6 movie premiere Kevin Winter/Getty Images

Pete Wentz and ex-wife Ashlee Simpson's son Bronx is all grown up! The nearly 6-year-old cutie attended the Big Hero 6 movie premiere with his dad and Wentz's girlfriend Meagan Camper in Los Angeles on Tuesday, Nov. 4. The modern family left Wentz and Camper's newborn baby boy Saint Lazslo home for the evening.

Bronx, who has ditched his signature blonde curls, donned a punk-looking tank as he stood alongside his smiling dad, who rocked a newly dyed and shaved head. Camper, dressed in a leather jacket and black hat, joined the father-son duo for the cute photo op in front of Disney's latest character Baymax.

An eyewitness tells Us that Camper, who welcomed her first child Saint on Aug. 20, "is really motherly towards Bronx" and was "watching him constantly and encouraging him to pose with her and Pete" on the red carpet.

"Pete and Meagan act very much as a family unit," the insider added.

Simpson and Wentz split in 2011. On Aug. 31, Simpson said "I do" to Evan Ross, where Bronx helped walk her down the aisle along with her dad Joe Simpson.

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