I have a 9 year old Amstaff, and within the last year or so I've noticed that he's been slowing down quite a bit. He was never a super cuddly dog, but he used to jump up on the couch with my wife and I to watch tv/ movies, and now he likes to just sleep on the foot of our bed all by himself. Also, we have always let him sleep on our bed, and he used to cuddle right up to us, but now he only cuddles up if you tell him to. It's kinda bumming us out. Is this normal for a dog of this age to start being like this?