The apsara Punjikastala was cursed to be a monkey. Her curse should be released when she gives birth to a son of Shiva. She asked Shiva for a son and gave birth to Hanuman, the monkey who became Rama’s ally in Ramayana. As the son of Anjana, Hanuman is also called Anjaneya.
It was Vayu, who brought the semen of Shiva into Anjana, so Hanuman is also called a son of Vayu. The story is found in the last of the links.
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