Sapphire of the Stars was born on the Comet Observatory shortly before Mario's visit. He guarded the Fountain at the Comet Observatory. He had three siblings: Opal of the Stars (Pink Luma), Ruby of the Stars (Red Luma), and Topaz of the Stars (Yellow Luma). His biological parents were Emerald of the Stars (Mother; Green Luma) and Amethyst of the Stars (Father; Purple Luma and Prankster Comet Know-It-All).