Mythology & Beliefs: Thyestes In Greek and Roman Mythology, Thyestes was the brother of Atreus; Atreus killed three of his sons and served them to him at banquet.
Thyestes in Greek and Roman Biography and Mythology
（Θυέστης), a son of Pelops and Hippodameia, was the brother
of Atreus and the father of Aegisthus. (Horn. Il. 2.107;
Aeschyl. Agam. 1242 ; Eurip. Or. 1008 ; comp. ATREUS ; PELOPS;
AGAMEMNON.) - A Dictionary of Greek and Roman biography and
mythology, William Smith, Ed.
Thyestes in Wikipedia
In Greek mythology, Thyestes (Θυέστης) was the son of Pelops,
King of Olympia, and Hippodamia and father of Pelopia and
Aegisthus. Thyestes and his twin brother, Atreus, were exiled
by their father for having murdered their half-brother,
Chrysippus, in their desire for the throne of Olympia. They
took refuge in Mycenae, where they ascended to the throne upon
the absence of King Eurystheus, who was fighting the
Heracleidae. Eurystheus had meant for their lordship to be
temporary; it became permanent due to his death in conflict...