I rehomed a young collie pup nearly 2 years ago. Was meant to be a working dog but failed everything! :) He is the best family dog we could ask for, but he is 2 tomorrow & still looks & acts like a puppy. Think a pup 9 months old. He has had all his vet checks etc, no health problems, vet said it is because he is the litter runt.
Anyone else have any experience of this? We do advanced level dog training every week etc