Base on what? She left momo side two occasions. To the samurai, to ace, and her father She has said, countless she wants go adventure just like oden once did. Luffy was one who had order to look after momo. Yamato is more person who is eager for fight than baby sit. she doesn't want to stay look after momo She has said, openly she wants join Luffy and rest of the strawhats. Carrot is barley relevant in this arc has not gotten screen devote herself character. She can barley keep with the other members of the crew.