When I was about 18, I joined the Army. We had a little Jack Russel at home. I was gone for 6 months at a time and he ALWAYS remembered me when I came home on leave. He'd be outside the front door, looking like he had a big smile on his face and wagging his whole butt!! I loved that little guy! He lived to be 17 years old. He was such a character. He used to sit on the Zebra crossing and wait for the cars to stop for him! The local butcher used to give him bones bigger than he was
LoL! I don't believe that dogs ever forget the ones they love. I don't think there's a time limit on it either.