The goal of this multi-method study was to examine how child gender and coparenting processes influence associations between family stress and toddlers' social adjustment. The participants, 104 dual-earner couples and their 2-year-old children, were videotaped in their home during a freeplay activity. Mothers and fathers completed questionnaires about stress in their roles as partners, workers, and parents and their child's social-emotional adjustment. Consistent with previous research, higher levels of family stress were associated with poorer adjustment for children. Family harmony, represented by warmth and cooperation, was significantly associated with fewer internalizing problems for children even when family stress was considered. Conversely, coparental banter or "playful humour" between parents moderated the nature of the association between family stress and children's adjustment. Banter between parents was especially protective for girls suggesting that, even in families with toddler-aged children, gender plays an important role in family-level coparenting processes. Future research needs to consider more fully the impact that child characteristics, such as gender, have on the interplay between the family context and children's development. (Contains 6 tables, 3 figures, and 1 note.)