Curate, connect, and discover
There have been a string of thefts in Gotham (which isn't unusual) that were confusing Batman, all involving things for a wedding. There were no finger prints, no signs of break ins and no cameras caught the thief. After finding out what the thief would steal next he placed a tracker on it.
When the thief stole it Batman followed it to a graveyard. While staking it out he saw a young girl around 5-7 with violet eyes commanding a floating boy with white hair around the same age, to set up the stolen objects in a way that resembles a wedding.