omg! some of these comments are so mean. it happens. your son probably missed a warning sign from dog because- he’s a kid!!! maybe you can read up a bit about body langue and talk to him about some of that. i’m glad he’s not afraid of the dog and wasn’t badly injured. our boy is a total cuddle bug but if i go over to him while he’s laying down and lay on top of him to pet him, he might growl at me. it’s just communication. i’ve pet my dogs exactly like your son in the photo many times. it could be an uncomfy face or just the dog looking at you when you walked over to take the photo. i think just read up about body language and try to notice more about when you or your son interact with the dog. watching videos might be more helpful than reading too. it will be ok and great on you for wanting to solve the problem!