Who is Dionysus related to?

Father: Zeus

Mother: Semele

Siblings: No full siblings

Half-Siblings: Athena, Apollo, Artemis, Hermes, Hephaustus, etc.

Aunts: Hestia, Demeter, Hera

Uncles: Poseidon, Hades

Grandparents: Cronus and Rhea

Great-Grandparents: Gaea and Uranus

That's just the immediate family, but I hope it helps!