Sunstar was an official leader of ThunderClan (one of four). Duskstar/Redstar, his brother, founded ThunderClan. He was made official leader after Redstar was killed, and he won a competition between him and Moonstar. He later gave his official leadership to his brother. Later, he became deputy of his brother. Subsequently, he quit ThunderClan, and joined The Pack of Desolate Sins. After his leader disbanded the pack, he joined TC and now remains there. He has lost and eye, and now is an elder. He was 113 moons (9 years old) when he passed away of old age along with his friend Amberstone.