Dogs are very cute when they dream - those little high pitched barks (it always fascinated me that Lotlot barked in her dreams when she hardly ever barked in waking life) and growls, the shivers and trembles.
Today Mr V did something I've never seen before - he wagged his tail vigorously while sound asleep. He was lying spreadeagled across our bed while I was reading. Suddenly his tail lifted up and moved to one side. Then it went back to the middle. Then it went wag, wag, wag, wag, wag, wag while he otherwise lay perfectly still and silent, eyes firmly shut. What a happy dream! Maybe he was remembering something like this.