Ashlee Simpson  brought baby Bronx out to watch his dad perform on stage with Fall Out Boy on Friday night in Mesa, AZ. She had a huge smile on her face while keeping her son's ears protected with cute oversized headphones. Pete was back on stage in Laguna Hills on Saturday, while Ashlee returned to LA and tweeted how much she missed him . At least she has Pete's rock star mini me to put a smile on her face and ward off rumors of unhappiness  from the new mom.
Source  and Ginsburg/Spaly Inc