In an interview with Koichi Hayashida... “This is maybe a little bit of a strange story, but we never really went out of our way to decide on the sex of these characters, even though they have somewhat gendered appearances,” Hayashida said. “But I think what I can say is that Toadette and Toad are not siblings -- perhaps it would be more accurate to say they are adventure pals. And that’s certainly true here [in Captain Toad].”

Hayashida also clarified that Toads are not mushrooms.