unfortunately, sometimes it does excalate tho. Insecure dogs, and a lot of that can be genetic, will often worry if they have something they don't get often and/or if it's high value.
Besides, unless your intention is to pin the dog in a corner and beat the cr@p out of it, there's no reason for the situation to escalate.
or you could teach the dog to be nice about it and give it up w/o worry.
Back to the OP's dog -- since the child is so young I wouldn't give the dog anything it felt the need to guard. Perhaps the dog is "afraid" of having its chew taken away but it's not afraid of the child. Thus the growling. Otherwise it would run off with the chew in its mouth. I doubt that the child had the dog so firmly cornered that there was no possibility of escape. (insert eye roll here)