Question: is te fiti moana grandma?
Answer: [Moana] Moana is a descendant of the demigod of Te Fiti. So the long and short of it is just that: Moana and her ancestors are descendants of a demigod of Te Fiti. In the movie we see Moana's grandmother exhibit some mystical properties. When she dances in the ocean the rays obey her and dance with her.