I can't believe I'm going to comment on something so ridiculous, but Imprinting...
To quote Twilight Saga Wiki, "Imprinting is the involuntary mechanism by which Quileute shape-shifters find their soul-mates. "
I believe it was in the first movie where Jacob talks to Bella about it, and mentioned at the Quileute will be whatever they are suppose to be to the person, if the person happens to be a baby. Spoiler Alert!
So, basically, Jacob and Renesme are soul mates and will together forever.
(Yes, I've read and watch all of them. They are my ridiculous guilty pleasure that I complain about. So many issues...)