So last night we walked down to my kids baseball game. As I was sitting there with Rosko a 3 yr old girl who has petted and played with Rosko on numerous occasions asked if she could pet Rosko. I as I always have said sure. I had rosko sit and the little girl walked up to Rosko's right side and started to pet his right shoulder. After about 2 seconds Rosko turned and growled / barks at the little girl. I had his leash pretty short so I was able to instantly pull him away from the girl and correct him. He lay down and in a few minutes seemed fine so I let him up. He was fine the rest of the game the girl approached about 20 minutes later with a stick for Rosko which he took just as gentle as I would expect him to. She pet him numerous times after the incident and he was fine. The only thing different about him was his barking. Not at anyone in particular just out in the field behind the diamond at birds. He usually doesn't do that. There was no warning to the incident just a, quick turn and growl, bark. He didn't actually snap at her. If he had wanted to bite her he certainly could have he just wanted to let her know that something wasn't OK. His tail was on that side I suppose she could have stepped on his tail. (NO EXCUSE). Other than that I have no idea why the nut would have acted that way. He is 13 months old. Think it could be hormonal changes, the new puppy adding stress, combo of both?. And trainers was I right to let the girl pet him half hour after he freaked. I felt that he learned from my correction that was unacceptable. I thought if I said no it would be worse for the situation.