Only 50% of non-breeders in a colony typically become helpers, and whether or not an individual becomes a helper and to whom it provides aid is heavily dependent on the degree of kinship involved. Non-breeders are most likely to become helpers when breeding pairs are close genetic relatives. When faced with a choice of potential recipient nests, helpers preferentially help the breeding pair to whom they are most closely related, suggesting that this behaviour may serve to increase the helper's inclusive fitness.