Who are the Greek god Poseidons siblings and what were they the god of?

Answer 1

The children of the Titans Cronus and Rhea:

Hestia, goddess of the hearth (both private and municipal) and the home, fire, and feasting.

Demeter, Olympian goddess of agriculture, grain, and bread, the prime sustenance of mankind.

Hera, queen of the gods and the goddess of women and marriage. She was also a goddess of the sky and starry heavens.

Hades, King of the Underworld, of death and the dead. He presided over funeral rites and defended the right of the dead to due burial. Haides was also the god of the hidden wealth of the earth, from the fertile soil with nourished the seed-grain, to the mined wealth of gold, silver and other metals.

Zeus, king of the gods, the god of sky and weather, law, order and fate.

The children of Cronus and Philyra :

Chiron, immortal Centaur god, teacher of heroes.

Aphros, immortal Ichthyocentauri (Fish-centaur), wise teacher who helped Aphrodite ashore; also the first King of the sea-going Aphroi (Carthaginians).

Bythos, immortal Ichthyocentauri (Fish-centaur), red-skinned; otherwise unknown.

Dolops, son of Cronos and Philyra, otherwise unknown.

Answer 2

Zeus, Hades, Demeter, Hera, and Hestia