Ben is a character that only makes an appearance in I Don't Believe in Mermaids. His parents took the opportunity to travel the south pacific, sailing for two years and wanted to take him with them. He didn't want to leave his things and friends. Nixie had given him advice to look after himself, trying to make him stronger.
Ben ran away the day after he first meet Nixie. Nixie then tracks him down and shares her secret with him. Ben does become friends with her and promises to keep her secret. Nixie watches him, as he leaves the coast. Ben knows that mermaids exist and delivered Sirena's present, she had made, for Aquata.