When Huntress' family is killed in Birds of Prey, one of them gives her a purple toy car, which seems to be a sign that it had a some importance to her or her family. Later on in the movie she gives it to Cassandra Cain before the climatic final fight, and is finally given back to Huntress at the taco place.
I feel like I missed something about it. It's continued presence gave me the impression it would become relevant but I cannot recall any dialog about it beyond characters saying "take this". Did it have any significance beyond being a keepsake?