Our 7 month old springer has started growling recently. We have been giving him natural chews (lambs feet, pizzles etc) for a while and he was crunching through them quite happily, but recently he has stopped eating them and instead just walks around with them and guards them. If dh or I approach him when he has put one down he will quickly pick it up again as if we are going to take it off him (which we never have). If ds3 so much as looks at him when he has one, he will growl. I have no idea where this has come from, can’t think of any triggers at all. Is this something to be worried about or is it a normal phase that he will grow out of?