I'm sorry about your grandpa, Scrooge.
Regarding his hearing loss, if it was sensorineural (progressive, usually caused by illness, injury or aging) chances are his loss was in the speech frequency range. That's where Tori's is, and it's often very confusing for people. She hears music fairly well, and odd noises that others don't pick up, but the spoken word is hard for her. I'm glad she can enjoy music, but there is so much that she misses out on!