It was her eighth birthday.
She'd just turned eight, and Mother had set the party in the newly founded Natural History Museum of Republic City, home of what had then been the only complete Tyrranodactyl skeleton known to human-kind. The celebration was the typically over-the-top Mother gesture. All sorts of entertainments were present: balloons, clowns, dancing lemurs, earth-bending demonstrations. Nothing less than the best would do for the Chief of Police's daughter.
Then, Mother, after partaking of a bit too much rice wine, invented yet another type of Earthbending.
There was little warning of the impending accomplishment except for Mother's authoritative voice telling everyone to step back. Her feet—bare as always—pounded the floor, and her arms spread open, and then clapped shut. The wire cables holding the Tyrannodactyl skeleton snapped, likely because the skeleton had just flapped its bony wings. Mother opened her arms and completed the motion.
The reanimated skeleton took flight around the enclosed museum crashing into priceless artifacts on loan from Ba Sing Se—including a rare and precious bear skeleton—before finally escaping through the skylights. For the grand finale, the Tyrannodactyl crashed through the front door of the museum and bowed towards the guest-of-honor before settling in a pile of dust at Lin's feet, coating her with a combination of dust and debris.
Of course, Kya and Bumi thought the whole display was the best thing ever, and once they thought something was great, everyone else followed. Even her normally sensible and dependable best friend Tenzin grinned before Lin glared some sense into him.
Her birthday party ruined alongside tens of millions of yuans worth of property and Mother wouldn't even be arrested if only because unregulated Fossilbending hadn't yet had the chance to become illegal.
Mother didn't even apologize when Lin scowled at her. Mother just ruffled Lin's hair and shrugged. "Well, I thought it was cool. The problem is: kids these days just don't know how to have fun."