I actually felt like I was 'watching' a Criminal Minds episode while I was reading this, especially once I got to the point where Derek was leading McKenna through the cognitive interview. I feel like you wrote McKenna's character very well and it's very believable. The terror and the pain she felt obviously wouldn't go away instantly. Criminal Minds always had a way of making you feel a little sorry for some of the unsubs and you've done the same thing! Obviously there's no excuse for what he did but you can tell he's just so broken over losing his little girl. And keeping in touch with McKenna seems like something Derek would do.
Definitely a good read!