A woman approaching middle age yet still childless decides to get pregnant by artificial insemination only to discover that the donor she chose may not be the father of her child in this comedy starring Jennifer Aniston & Jason Bateman Wally Mars (Bateman) is a dyed-in-the-wool pessimist Hopelessly neurotic & unrepentantly narcissistic he gets no joy out of life except for the time he spends with his best friend Kassie (Jennifer Aniston) However despite the fact that Wally pines to be more than just friends with Kassie she isn't convinced they'd make a good couple When Kassie announces to Wally that she's found the perfect sperm donor he's crestfallen; as far as he's concerned the ideal candidate is standing right in front of her Later Kassie selects handsome stranger Roland (Patrick Wilson) to provide the seed Things get complicated when Kassie's best friend Debbie (Juliette Lewis) throws an insemination party to commemorate the big event & Wally intercepts Roland's special delivery drunkenly replacing it with his own before blacking out Pregnant & content Kassie leaves the city for Minnesota where she gives birth to a healthy baby boy Flash-forward seven years & Kassie returns to New York with her son Sebastian (Thomas Robinson) who shares an uncanny number of physical & psychological traits with embittered bachelor Wally Before long Wally & Sebastian have become good friends & Wally becomes convinced that the boy is his biological son His ideal family is finally within reach & if he can just figure out a means of breaking the news to Kassie gently perhaps she'll find it in her heart to forgive him & recognize that he'll make the perfect father for Sebastian