As children Marie and Helen were inseparable friends. Now as adults, they are bitter rivals, but must see each other because Marie's daughter Katherine (Courtney Cox) and Helen's son Phillip (John Terlesky) fell in love and got married. When Katherine announces she's pregnant, both mothers seize upon the opportunity to outdo the other in attention, affection and financial support. When the baby is born, the grandmothers' rivalry intensifies. Katherine and Phillip are overwhelmed by the pressures of parenthood and work, the feuding grandmothers don't help the situation. Angry words turn into a heated argument and Phillip walks out. Both grandmothers are terribly upset about the rift between their two children and they are sure the other one is the cause. The grandmothers fight bitterly, unearthing some long-buried secrets in the process and forcing them to confront the foolishness of their rivalry. Having set aside their own differences, the grandmothers are ready to join forces to save Katherine and Phillip's marriage. The angry young couple is no match for the combined powers of their mothers - two old friends.