Medical student here as well. I know that most born deafness in the western world is caused by a mutation in a certain Connexin. I dont remember the particular gene but it can both be autosomal dominant or autosomal recessive. So if she has the dominant form that would give you 50-25% risk or else there risk is probably 0%. Since you dont have the defect gene. From what I read it sounds like an autosomal recessive form, so nothing to worry about.
But at least get it checked! Good luck.