Medusa father was phorcys a god of sea her mother was ceto also a god of sea and his sisters were gorgons and her other sister was graeae
Poseidon, the god of the sea, saw Medusa and let her into the temple of Athena. They both became in love.
Athena was disappointed with her that she fell in love with Poseidon he turned her hair into locks of snakes
and every time someone looked at medusa they turned into solid stone
The only way she could die was is someone did not look and her and was able to kill her by cutting her head off and as Perseus slashed her head off and as he did it a pegasus came out of medusa's head and all of those pegasus that came out were These were the children of Poseidon.