Daniel Reeves. He was a young man that Hotch knew personally. He was the victim of a elder couple and was forced to help them kidnap children. He could've escaped long ago, but chose not to. Because of Charlie. Charlie was his little brother who he would do anything for. Of course they weren't blood related but that didn't make it and less real. The team saves Charlie, and the three others, but they gave Daniel something better, they gave him hope, gave him a reason to continue life. They gave him a chance to help people, to do what he wanted to do, to save people.