Game of Thrones
This Baratheon princess met quite an ill-fate, so maybe it's for the best that she was recast before that happened. Aimee Richardson was usurped by Nell Tiger Free and lost her crown during season 5. A harsh but true rumor--Aimee found out about her replacement during the middle of a panel in ComicCon.
Jane the Virgin
Matteo is the beloved only child of Jane from the hit sitcom Jane the Virgin. Like most child actors, growing up means growing out...of your acting job that is. Little Elias Janssen replaced Joseph Sanders as the baby that captures Jane's heart. He was too busy with school and childhood to be bothered for the part.