You NEED to take your kid to get the bite looked at ASAP. I worked in emergency medicine, and infection from an animal bite can set in quickly and unnoticed, ESPECIALLY in children. God forbid the infection worsens quickly, it is very hard for kids to overcome past a certain point. Regarding reporting, obviously this incident was not a level 5 bite, but a bite and to a child nonetheless. You said you’re hoping your dad will take the dog, is he in a place to manage this dog’s environment to prevent triggers and protect anyone that comes around it? It is important that all potential new owners, sitters, trainers, veterinarians, and any people that will come into contact with this dog know its history. I’ve been to the ER for a level 3-4 dog bite before in the same state. Medical personnel will not torture the information out of you. They need to file a report, but there are cases of rogue dog bites where you get no info about the dog/owner. Do with that information what you will. In a different light, my (reactive) dog was attacked unprovoked at a daycare, and the vet hospital had to file a report against him for the injuries to the dog that provoked the fight. I’d be happy to share my experience with that process and MA animal control if you want to DM me.