Elsewhere,
I've never had to handle a situation likes yours because I'm (was) about the only JW in the family, so I offer you the best I have, sympathy. What I experienced before my Mum passed away 3 years ago, past 91, and found it very comforting, was staying with her as much as I could, every evening, because we both knew that time was getting precious. It was a comforting feeling, afterwards, to know that I had done as much as I had been able to, and I believe it was a solace to her to see 2 of her 3 children, and one of her grand daughters, near her in those instants. I'm sure that your JW family won't bar you from doing so, JWs as they are, they are humans and, who knows, you might get closer to one another in these circumstances. My best wishes to you, and to your Dad.
A thought for Purps who hasn't had a chance to draw closer to her Mum last WE.