Despite emotion researchers’ strong interest in empathy and its implications for prosocial functioning, surprisingly few studies have examined parent–child attachment as a context for early origins of empathy in young children. Consequently, empirical evidence on links among children’s attachment, empathy, and prosociality is thin and inconsistent. We examined such links in 2 longitudinal studies of community families (Family Study, N = 101 mothers, fathers, and children, 14 to 80 months; Parent–Child Study, mothers and children, N = 108, 15 to 45 months) and a study of low-income, diverse mothers and toddlers (Play Study, N = 186, 30 months). Children’s security was assessed in Strange Situation in infancy and rated by observers and mothers using Attachment Q-Set at toddler age. Children’s empathy was observed in scripted probes that involved parental simulated distress. Children’s prosociality was rated by parents (Family Study, Play Study). Security with mothers related to higher empathy. For mother- and father–child dyads, security moderated the path from empathy to prosociality. For insecure children, but not secure ones, variations in empathy related to prosociality. Insecure and unempathic children were particularly low in prosociality.