I personally would have it docked unless you already have someone lined up to adopt him and they don't mind having a long tail on their pup. I found it is harder to place them in good homes if their tails aren't done. People have a picture in their head of what a yorkie looks like and it usually doesn't include a long tail. Cograts on your new pup. I also had a litter of 1 after litters of 4. (It wasn't a yorkie litter though.) Just make sure to keep the pup warm with not having bothers and sisters to cuddle with they get cooler quicker. Good luck.
