There are products that are designed for small canine breeds but these are especially designed for adult canines, not puppies. (mypetneedsthat.com)
This falling off of litter size at a certain point doesn't typically apply to females of especially small canine breeds, however. (dogcare.dailypuppy.com)
She was believed to be female because she had a relatively small skull and small canine teeth. (sciencenewsforstudents.org)