hello bonbask,
sounds like your dad is in pretty good shape for almost 100. the last lady I took care of would have been 101 years old. she was amazing, extremely sharp, what a memory better than mine. She had some awesome stories to tell. She also, for the most part, stayed on her own except for the last year of her life which I stayed with her for five hrs five days a week. She took quite a few meds, which her grandson set up for her and he also stayed with her at night, because she didn't want to be alone then. Anyhow, she truly enjoyed my coming to stay with her those few hours every day. It gave her some companionship, some help with her bathing, she helped prepare lunch and several times during the wk we would have company for lunch. We baked cookies, did some gardening. She was always sad to see me go, especially on wkends, her children and grandchildren told me how much she had perked up since I had started staying with her. I guess what I am saying is she still enjoyed doing a lot of things she just needed a little help.