Stephie has an odd family with weird rules, like no playing alone. So when Stephie's brother Peter catches her playing alone in the tree house, he has no choice but to join in on the fun. But when dad comes home and finds both his son and daughter playing together, initially he's proud, but then Peter snitches on his sister, admitting that she was playing alone. That when dad decides to join in to see exactly what mom's been teaching these two while he's at work all day.