Hecate was born to Perses, Titan of destruction, and Asteria who was the daughter of Coeus and Phoebe.
Asteria was the sister of Leto who’s the mother of Artemis and Apollo, making Hecate their cousin.
Perses, Hecate’s father was the son of Krios and Eurybia.
Krios or Crius was on of the original children of Gaea and Uranus, so he was the brother of Cronus.
Cronus, being the Titan father of the gods would be Hecate’s Granduncle, making the six children of Cronus; Hestia, Demeter, Hera, Hades, Poseidon, and Zeus her second Aunts and Uncles.
Hecate’s major godly cousins (distant or otherwise):
Athena
Hermes
Persephone
Ares
Hephaestus
Diyonisus
Apollo
Artemis
Godly Aunts (distant or otherwise):
Hera
Demeter
Hestia
Godly Uncles (you get the idea):
Hades
Poseidon
Zeus
Children:
Circe
Pasiphae
Scylla
Empousa
Aeëtes