Let's just say that Naruto's conversation with him was ever so much more poignant when I had more details than what I'd extrapolated from "Asshole father stuck him with a sand demon."

Also, since I had terrible insomnia for a number of years before I discovered exercise, that thing about not being able to sleep because the demon eats your personality if you do really freaked me out. No shit that would make you "unstable."

There's a tiny little scene, after Naruto comes back with Tsunade, when he and Iruka are eating ramen at their usual joint and Naruto, with his mouth full of ramen, is saying something like, "And then I used my new improved jutsu, and all the bad guys went flying!" and Iruka gives him this look like, "You are such a dork and I love you so much." It was just the sweetest thing ever.