wow, 19 years... I think it's everyone's dream to have a dog live that age. He must have had a wonderful home
. The little puppy is probably adjusting to the new place, I'd definitely take him to the vet, for a check up and the vet should tell you what to do next (and I'm sure you'll receive a great load of information here as well). When I got Pepper, his stools were 'funny' for almost a month and he wouldn't eat sometimes. The vet OK'd him so I guess it was a puppy thing.