Yes they do remember, it might take a minute or two but they do. My husband was in a mobile unit in the Air force for 10 years and would be gone for months (4-6) at a time. Each time he returned my dog would be cautious around him for about 2-10 minutes then would absolutely go crazy when she realized her "daddy" was home! This was her life from the time she was 8 weeks old, so I think your puppy will be fine.
