Donovan’s Big Day by Lesléa Newman
Plot Summary: Donovan's two moms are getting married, and he can't wait for the celebration to begin. After all, as ringbearer, he has a very important job to do. Any boy or girl with same-sex parents—or who knows a same-sex couple—will appreciate this picture book about love, family, and marriage. The story captures the joy and excitement of a wedding day while the illustrations show the happy occasion from a child's point of view.
Youtube link to a book trailer which gives you a sense of the illustrations and tone: https://www.youtube.com/watch?v=j7n1R3sFiPI
Donovan is super excited about getting dressed up for the wedding. The story focuses on this more than the fact that it’s his two moms getting married. Indeed, the plot would be unaffected if you substituted two moms for two dads or for a mom and a stepdad or a heterosexual parents’ vow renewal or any other variation.