Here is my experience with my island.
Me (Narie) - I am female IRL and have a female character.
Luna - My sister's character, she is female IRL and has a female character.
Masami - My husband. He is male IRL and has a gender neutral character, though technically selected boy during the creation process.
Lysassarin - My brother in law. He is male IRL and made a female character.
My sister and I typically create female characters, my husband typically creates either or, it just depends on his mood and my brother in law typically creates female characters.