Studies from diverse cultures report mixed results in the relationship between birth order and risk for obesity. Explanations may thus lie in the postnatal period when growth is shaped by the family environment, including parental feeding practices, which may be affected by siblings. Consistent with a family systems perspective, we describe two processes that may explain birth order effects on parental feeding practices and child outcomes: learned experience and resource dilution. Parents learn from experience when earlier-born children influence their parents' knowledge, expectations, and behavior toward later-born siblings through their behaviors and characteristics-which can have both positive and negative implications. Resource dilution is a process whereby the birth of each child limits the time, attention and other resources parents have to devote to any one of their children. The goal of this review is to provide a theoretical basis for examining potential sibling influences on parental responsive feeding toward developing recommendations for future research and practice aimed at preventing obesity throughout family systems.
Keywords: family systems; parenting; responsive feeding; siblings.