Have they EVER pooped? I ask because there was a member here at one time who had a litter and a couple of them had deformities where they didn't have anuses, or rather there was no hole there for anything to come out. I imagine you would have noticed this with massaging, though.
"Be who you are and say what you feel. Because those that matter, don't mind...And those that mind....don't matter."
How old are these pups? I know you say they haven't pooped in a day and a half but how often are you feeding and what are you feeding?
The reason I ask about YOU feeding instead of mom is because in my experience with Bullys, the mom usually does nothing. Now keep in mind, that is only my experience but I've always watched the owners do all the feeding and caring for the puppies. Especially if she had a c-section. But as already mentioned, mom might be cleaning up after them if she is with them. If this is not the case, a trip to your vet is probably a good idea.
Best of luck with these 2 babies, they can be a real chore but they are adorable and very loving.
Friends will step in when the rest of the world steps out.