Kind of depends on how much of each characteristic the kids get. THey could be more pygmy and be small or more nubian and be bigger. Or fall right in the middle and be mid size. I wouldnt expect them to be a small as your pygmy though.
Well I also think it depends on how many kids she has. I had one Nubian have triplet kinders and they were smaller when full grown but they are bigger than the Nigerians. One mom had a single and she was bottle raised and she is almost as big as a nubian. Some have airplane ears, some have long ears and some have upright ears. You just never know what you are going to get. I bred my kinder back to a nigerian and got smaller kids but still bigger than the nigerians even with quads born. Hope that helps.