Remus sees James, when he looks at Harry. Apart from the eyes, he's so much like his father it's frightening. That took quite some getting used to, and for some months, Remus had to watch his words, so he didn't accidentally call Harry by the wrong name.

He's come to view it as a second chance. He lost James to Lily, to adult responsibilities, and to death. But death will not take Harry, if he has anything to do with it. Perhaps he couldn't save the man who was once his lover. But by Merlin, he *will* protect James' son.