I have a similar pattern in my family. My mother was only 41 when she died. I've had three sisters die at ages 34, 52, and 56 respectively. I am 50 and I have a niece who is 52, so she's now at the age when her mother died. She and I were having a discussion how none of the women in our family make it out of their 50s alive.
Of course, she was discussing it from the viewpoint that she was worried about dying.
I, of course, couldn't express my ideas that I find the idea of not making it out of my 50s comforting. However, since I just turned 50 last year, I don't want to have to wait for nature to take it's course. I'd rather help it along. I had really hoped that I would've died by this point already. I didn't even want to make it to 50, and I certainly don't want to make it to 51.