Katherine Heigl and Josh Duhamel really nailed this one. This story of friends turned family shows that love can be found in the most unexpected places and brought about by the most tragic of circumstances.
Holly Berenson and Eric Messer aren't exactly friends. They only have two things in common: their mutual dislike for each other, and their love for their goddaughter, Sophie. However, when Sophie's parents (and Holly and Messer's best friends) are killed in a car accident, the not-so-friendly pair must come together to provide for the little girl. Neither planned on giving up their lives, but soon they find themselves living together in Sophie's house, doing their best to raise her.
It takes a while, but the two start to warm up to each other. Their love of Sophie brings them together, and soon their dislike turns friendship. Before long, the friendship starts to transform into stronger feelings, but when Messer is offered a job in Phoenix (a long way from their Atlanta home) and eventually takes it, it rips the two apart. However, it doesn't take long for the two to realize their split was a mistake. All the while, Sophie lives and learns, and comes to know the pair as the only family she has.
This really is an excellent movie. It's the kind that has the ability to send your emotions all over the place. One minute your heart is aching and the next, you find yourself laughing your butt off. I highly recommended it.