mmm a personal headcanon? If we’re doing ATLA, I’ve always believed that Katara stuck around in the Fire Nation to help Zuko during his first several months of reigning. He had a catastrophic injury and she’d want to monitor him, even after he insists he’s okay. After she’s assured he’s alright, she goes to the Southern Water Tribe, where she stays until she’s 19/20. She keeps in touch with everyone, occasionally visits Iroh and Toph, and journeys to Caldera once a year for the Festival of Lights.