In early mythology, he was portrayed as a son of Ra.[24] In the Coffin Texts, which were written in the First Intermediate Period (c. 2181–2055 BC), Anubis is the son of either the cow goddess Hesat or the cat-headed Bastet.[25] Another tradition depicted him as the son of Ra and Nephthys.[24] The Greek Plutarch (c. 40–120 AD) stated that Anubis was the illegitimate son of Nephthys and Osiris, but that he was adopted by Osiris's wife Isis:[26]