(Jenn gave me permission to share Peter's writing with you.)
Of course, I don't know what conversation, if any, transpired between Peter and his teacher. Maybe she did tell him how proud he made her feel and how his words moved her. I just wish that's what would have been left behind on a piece special enough to share on social media and probably cherish for a long while.
Personally, I don't believe in writing on my students' writing unless we're preparing to publish. They edit as much as they can, and I edit the rest for free. Otherwise, my writing utensils don't touch their work. (I understand that in the upper grades written comments can be useful.) As a writing teacher, I must tread carefully though. Of course I want to nudge my writers, which I can do without writing on their work, but I must also inspire them. I cannot nudge or inspire, if in the end, they do not remain intact.