Tilly has been fine for a while. If she greets other dogs, she’ll sniff them and wander off. She’s very good at coming back if I sense a stand off with a dog. As soon as I call her name she comes straight back to me. Today, however, she met a larger dog, sniffed for a bit, then snapped and growled with seemingly no provocation at all! The other dog just backed away afterwards (it was a male) Why is this? Does she sense something that I don’t sense? Do male dogs give off the indication they may mount before any action takes place? (She is spayed) I’m just worrying that this will happen more and more and I want to nip it in the bud before it progresses, or should I just let her tell off dogs that seem to do nothing as she may sense something about them I don’t know?