The mermaids in J.M. Barrie's Peter Pan spend their time lazing around the lagoon, brushing their hair, and admiring their reflections in the water. They do not care for any of the children in Neverland, except for Peter Pan, of course. The mermaids are all infatuated with Peter and long to listen to his stories of danger and adventure. 

Because of their feelings for Peter, they do not like seeing him with Wendy. They are jealous of the fact that Peter spends his time with another girl and bully Wendy because of that. When the mermaids encounter Wendy, they try to harm her by attempting to pull her in the water and splashing water on her with their tails. The 1953 adaptation of the book features a well-known scene in which Wendy and the mermaids first encounter each other. The mermaids joyfully welcome Peter back to Neverland and swoon over him until they notice Wendy calling Peter's name. Quickly thereafter, the mermaids begin to bully Wendy and claim that "they were only trying to drown her." While the 1911 publication of Peter Pan does not include dialogue between Wendy and the mermaids, the book does state that among Wendy's biggest regrets in Neverland was that "all the time she was on the island she never had a civil word from one of them." Wendy admired the mermaids, as she had heard of them in story books and had always dreamed to meet one in person. However, given the jealous and mischievous nature of the mermaids, Wendy was never able to form a friendly relationship with them due to their infatuation with Peter.