yes if you gave him a dewormer he should be defecating them.
I also have a yorkie Rusell, my son rescued a jack rusell girl, the rescue assured us she was spayed and guess what, she was NOT, my yorkie stud got to her and we had a litter, I kept the runt, my hubby fell for him after we had to hand feed him for a month..
this is Relay our Yorkie Rusell..
hugs, and welcome,
Carmen in nj