Missy sneaks out to a high school party with older kids. Mary finds out and grounds her, leading to a tense mother-daughter confrontation. Unlike Sheldon’s mathematical frustration, this conflict is purely emotional. Mary tries to control Missy’s behavior with rules, but Missy rebels by pointing out Mary’s hypocrisy (e.g., Mary hiding her own teenage mistakes). The resolution is not a clean equation but a messy, honest conversation where Mary admits she’s scared of losing Missy to adolescence. It’s a rare moment of raw parenting in the series.