Most of mine live to at least 69-71, but some die earlier than that. Like you I give them the best of care. I don't think there's anything else we could do to prolong their lives. I'd like to see them live to their 80's at least.

I think Arnie's right too about your peep getting ready to die when you picked him up, and that causing the game to lose him until you restarted it. It didn't have anything to do with your picking him up.