I am so sorry. I could not imagine seeing something like that. Let alone a child seeing it. Maybe ask the boy if he feels he could handle a new puppy now. Leave it up to him. I often think about that myself. I do think if it happened to me and I got another, I would constantly be comparing the new pup to Penny. She is one of a kind. Aren't they all! Again. I am so sorry.
RIP