Princess Celestia (Friendship is Magic)

Princess Celestia is the former Princess of Equestria who had the longest known reign of all Equestrian monarchs.

Early life
Celestia was born somewhere in the distant past, during the era in which such legends as Rockhoof and Mistmane walked the land. Although initially a pompous teenager who bullied her sister, Celestia's tune changed after Luna got trapped in the alternate universe where she was very nearly killed (and indeed, another version of Luna did die in this same scenario), afterwhich Celestia began to grow into her more kind and motherly nature.

Personality
Celestia in her younger years was a rude and self-absorbed individual. Though she did have a kind heart, her demeanor was far more condescending and mean-spirited, often talking down to her sister, causing her much insecurities. As she grew, Celestia became a much kinder, much more gentle individual with a sincere love for all Equestrians, though especially her friends and family. As graceful as she was, Celestia had an incredibly strong sense of humor and loved to play lighthearted jokes on her subjects and associates and even hosted her own annual comedy show.