We have Teddy and his sister, Ellie. They are mutts from the same litter. They didn't go to puppy kindergarten and we can't tell who is more dominant. Our vet said that since they have grown up together, neither might be particularly dominant over the other. They play well together. We thought that Teddy's howling might be the result of trying to protect Ellie which is why we're seperating them periodically on outings. Any suggestions?