Poseidon parents were Titan's Cronus and Rhea. He has five sibling there are Hestia, Demeter, Hera, Zeus, Hades He had one kid his name was Triton (sea god), then he had two more kids with his sister Demeter. There name's were Arion and a daughter named despoina. Then had two more with a woman named Medusa there names were Chyrsoar and a winged horse Pegasus. Then had two more but they were given to him by Gaia and there names were Antaeus (giant) and Charybdis (sea monster). So in all Poseidon has 7 kids in all.