Children's experience of chronic pain is influenced by the psychological and behavioural responses of their parents. However, the majority of research has been cross-sectional, precluding examination of how these dynamic relationships unfold over time. This study used a microlongitudinal design to examine the daily relationships between parent mood and protective responses and child chronic pain. We also examined the moderating roles of child and parent pain catastrophizing to determine how the affective-motivational context may alter the influence of parent factors. Participants included 95 youth with idiopathic chronic pain (M-age = 14.08; 71.6% female) and their parents. At baseline, parents and youth reported on their catastrophic thinking about child pain. For 7 consecutive days, parents completed daily assessments of their mood and protective responses, while youth completed assessments of their pain intensity, unpleasantness, and interference. Multilevel path analyses were conducted. At a daily level, greater parent protectiveness significantly predicted higher youth pain unpleasantness, interference, and intensity; more negative parent mood significantly predicted higher youth pain intensity and unpleasantness. Higher baseline youth pain catastrophizing predicted a stronger daily association between parent mood and youth pain unpleasantness and intensity. Higher baseline parent pain catastrophizing predicted a weaker daily association between parent protectiveness and youth pain interference. Findings suggest that parent mood and protective responses are dynamic, daily predictors of child pain. Findings also underscore the importance of addressing parents' daily mental health and protectiveness, among youth with chronic pain, and suggest different intervention targets depending on levels of child and parent catastrophizing.