This laboratory-based study examined lagged associations between child pain behavior and maternal responses as a function of maternal catastrophizing (CAT). Mothers completed the parent version of the Pain Catastrophizing Scale. Children participated in a validated water ingestion procedure to induce abdominal discomfort with mothers present. Video recordings of their interactions were edited into 30-second segments and coded by 2 raters for presence of child pain behavior, maternal solicitousness, and nontask conversation. Kappa reliabilities ranged from 0.83 to 0.95. Maternal CAT was positively associated with child pain behavior and maternal solicitousness, P values <0.05. In lagged analyses, child pain behavior during a given segment (T) was positively associated with child pain behavior during the subsequent segment (T + 1), P <0.05. Maternal CAT moderated the association between (1) child pain behavior at T and maternal solicitousness at T + 1, and (2) solicitousness at T and child pain behavior at T + 1, P values <0.05. Mothers higher in CAT responded solicitously at T + 1 irrespective of their child's preceding pain behavior, and their children exhibited pain behavior at T + 1 irrespective of the mother's preceding solicitousness. Mothers lower in CAT were more likely to respond solicitously at T + 1 after child pain behavior, and their children were more likely to exhibit pain behavior at T + 1 after maternal solicitousness. These findings indicate that high CAT mothers and their children exhibit inflexible patterns of maternal solicitousness and child pain behavior, and that such families may benefit from interventions to decrease CAT and develop more adaptive responses.