In
Greek mythology, Tereus was a son of
Ares and husband of
Procne. Procne and Tereus had a son,
Itys.Tereus desired his wife's sister,
Philomela. He forced himself upon her, then cut her
tongue out and held her captive so she could never tell anyone. He told his wife that her sister had died. Philomela wove letters in a
tapestry depicting Tereus's crime and sent it secretly to Procne. In revenge, Procne killed her child Itys and served his flesh in a meal to his father Tereus. When Tereus learned what she had done, he tried to kill the sisters but all three were changed by the
Olympian Gods into
birds: Tereus became a
hoopoe; Procne became the
nightingale whose
song is a song of mourning for the loss of her son; Philomela became the
swallow. Because she has no tongue she can only twitter instead of singing.
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