Better Together: Offspring Benefit from Siblings in Both the Absence and the Presence of Parents

, where we isolated offspring from siblings and/or parents, we showed that offspring benefited from the presence of both parents as well as siblings. The positive effects of siblings were evident in the absence and presence of parents, although they manifested differently. Without parents, growing alongside siblings resulted in higher larval mass at dispersal, perhaps due to advantages of collective feeding. With parents, having siblings accelerated early growth and increased survival, possibly due to higher begging activity, which may have influenced parental investment. Our results support the notion that beneficial sibling interactions are an important part of facultative family systems and may encourage offspring to stay in a family group.