The Switch

The film starring Jennifer Aniston as Kassie Larson, a single woman who decides to have a baby using artificial insemination. Her best friend, Wally Mars (Jason Bateman), is opposed to the idea, but he supports her nonetheless. On the night of Kassie's insemination, Wally gets drunk and accidentally substitutes his own sperm for the donor's.

Seven years later, Wally meets Kassie's son, Sebastian, and realizes that he is the father. Wally and Kassie begin to spend more time together, and Wally starts to develop feelings for her. However, he is hesitant to tell her the truth about Sebastian's paternity for fear of losing her.

Meanwhile, Kassie is dating a new man, Roland, who wants to marry her and adopt Sebastian. Kassie is torn between Roland and Wally, and she doesn't know what to do.

Eventually, Wally confesses the truth to Kassie, and she is furious. She breaks up with him and tells him that he is never going to see Sebastian again. However, she eventually realizes that Wally is a good man and a good father to Sebastian. She forgives him, and they begin to rebuild their relationship.

In the end, Kassie and Wally don't get together romantically, but they become a family for Sebastian. They learn to co-parent and love him together.

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