Life as We Know It - Greg Berlanti

Holly and Eric were set up on a blind date by their friends, Peter and Allison who are married. After Peter and Allison are killed in an accident, they learn that they have been named as the guardians to Peter and Allison's daughter, Sophie. So they move into their house and try their best to honor their friends' wishes. But raising a child puts a crimp on their style and they don't exactly get along.