Somehow, with all three of my daughters, they all pooped either on the same day or one or two days after peeing first in the toilet. They all caught on to potty training quickly, and there wasn't much of a difference with peeing and pooping. They all fully trained within a week of first trying to train them.
This may be TMI... This little girl I used to be a nanny to had a much harder time getting used to pooping in the toilet. She also always had hard poops. My children have hardly ever had hard poops. Maybe it wasn't a problem with my children because it didn't require as much effort to poop. I always took it as that. My kids' poops are always "formed" but soft. They have a well-balanced diet. The girl I used to watch did not have a well balanced diet. Maybe some prune or apple juice can help her get used to pooping in the toilet. This is just a thought to consider....