The son of Pete Wentz and Ashlee Simpson-Wentz turned 2 on Nov. 20, but Ashlee says he'll still have a nice Christmas – though they'll have to branch out in terms of presents.
"He just had his birthday, and he got a lot of gifts," the pop singer, 26, told PEOPLE on Monday at an Alice & Olivia toy drive in West Hollywood. "He'll still have a great Christmas, and he's really into Thomas the Train, but we have enough Thomas, so we do not need that this year!"
As Bronx gets older and more aware, his parents are beginning to develop family routines around the holidays. "For my husband and I, it's nice to start those traditions now," Ashlee says. "What we're doing with the tree, what we did over Thanksgiving ... we actually had an amazing Thanksgiving with Pete's family."
Looking to the future, those traditions will also include sister Jessica Simpson's future husband, Eric Johnson. Their relationship, says Simpson-Wentz, is as festive as anything this season.
"She is genuinely very, very happy, and you go to their house and it's warm and cozy, and it's a good feeling," she says. "And he's just a good guy."
And if Eric and Jessica happen to add to the family in the next few years, so much the better. "Of course it would be wonderful if it happened," says Ashlee. "We were actually over there yesterday, and Jessica is a wonderful godmother, and aunt, so I know she would be a wonderful mother."