Can a dog have one premature puppy and stop labor and other puppy at a later date?
i think this is impossible because a dog cannot just have one pup.the mom has to give birth to at least mabe 4-6 pups at one time. Yes, a dog can have one puppy (live or dead) and go out of labour for a few days. A dog can also lose one or more puppies without losing the whole litter. I know of several cases where a dog passed one puppy and had more in 2 to 3 days. Retained puppies and placentas can be very dangerous so always discuss anything odd with your Vet.
If your dog is pregnant and you aren't sure whether or not she is in labor, watch her behavior for a few signs. A dog in labor will be restless, circle, pant, and dig at her nest. She may have a discharge as well. If she seems distressed or appears to be pushing hard and no puppy appears, she may have a puppy stuck. Call a veterinarian for advice.
I have a bulldog myself! (Hence the Username) and he is very nice to my new puppy but with other dogs he just tries to be territorial. My puppy on the other hand is very nice and knows his place. In my opinion I think if you socialize your dog as a puppy they will be very nice to other dogs they meet.