Parenting research is frequently conducted without a thorough examination of socio-economic characteristics. In this study, longitudinal observations of positive parenting were conducted across six time points. Participants were 219 mothers of children with and without developmental delays. Mothers' positive parenting increased during early and middle childhood in children with and without developmental delays. Mothers who reported more education had significantly higher levels of positive parenting when their children were 3 years old. Mothers who reported more family income grew at a significantly faster rate in positive parenting. There was preliminary support that mothers with more income were more likely to be members of a class that started off and remained at a higher level of positive parenting over time. Implications are discussed.