Tokyo Godfathers (2003) on Netflix

Plot summary

Gin, Hana and Miyuki live on the streets of Tokyo as a family of their own making. On Christmas Eve, rummaging through the trash, they find a newborn girl, a note asking whoever finds her to care for her well, and a key to a locker that holds clues to her parents. Hana names the baby Kiyoko, after the Japanese title of Silent Night, and convinces the others to keep her overnight. The next day the three begin hunting for the parents, carrying Kiyoko across the city. They rescue a yakuza boss pinned under his car, and he invites them to his daughter's wedding.