Gary has the kids for Thanksgiving, but Allison wants all of them to spend the holiday together, including kids, grandparents and significant others.  Gary rejects Allison's idea, preferring to celebrate their first holiday as a divorced couple without his ex-wife. 

When Allison convinces Gary's dad to stay at her house, Gary retaliates by convincing her dad to stay at his.  When Allison's dad sees Gary's new single life, he decides he wants to divorce her mother.  Allison then takes Gary's turkey hostage and will not return it until Gary returns her father back to her house and mother.