My child has cysts on her kidneys, myself and her dad have not. so what could she have?

Recessive disorder: When neither parent have features of a genetically based disorder, they are silent carriers. Their offspring at any conception have 1/4 risk of acquiring a recessive disease. There is a recessive form of poly-cystic kidney disease. You should meet with a geneticist who can review any records you have and confirm or exclude this possibility. It could be something else.