I just wanted to let you know that if he was in such rough condition when you found him then he was either away from his family for a very long time, or they didn't care for him properly when they had him. If he has been away from his family for a great deal of time, don't you think you would have seen some kind of notice or poster in town? I think you should keep him. He seems very happy with you and it seems to me that his previous family either didn't care enough to care for him in the first place or don't care enough now to search hard enough for him. But, if you are feeling guilty, put up a couple of posters in vets offices or other reputable places. I'm sure this would make you feel better.
