"In the books, it happened ONCE, to Brightheart because Bluestar was loosing her mind a bit and was angry with StarClan."
May I correct you there? It actually happened many times. In Bluestar's Prophecy, happened to One-eye, who was named White-eye, and Halftail, who was once named Sparrowpelt. And it happened Crookedstar who was once named Stormkit, as well, in Crookedstar's Promise. In Tallstar's Revenge, Hopkit was renamed Deathpaw.