Sorry for your loss Dan.
I've never tried starting the same game again to see if they are going to live longer - but I do know from experience that if you start a game again different events happen.
My peeps lifespan increased after I started giving them only organic food. Maybe it happens because they got healthier with that. Oh, and when their health meter goes down I give them vitamins or that gel.
Yep been doing both as well when I logged off the night before he died I checked his health meter and it was almost 100% but

maybe he got sick over night I have no idea
oh well I may or may not restart it ... I might keep moving forward with it and hmm wonder if I can restart it in a second slot ?