THE LITTLE MERMAID 3: Ariel's Beginnings?

Okay i watched the movie and i don't get it. Maybe I'm a mythology geek but Ariel's mom's name was Athena ( I THINK ) and her dad'd name was Triton. OKAY. DIDN'T POSEIDON AND ATHENA HATE EACH OTHER??? I don't think that Athena would even try to get together with his son.