I will be an absolute wreck when it comes to handling this kind of stuff. My sister will be even worse, probably.
My dad is 77 and is doing ok. Mom is 69 and fine too.
My mom is concerned about my dad but his mom lived into her 90's and he takes after her in many ways. The concern is with memory stuff. Probably nothing to be all too concerned about... but... example. Wife was at my sister's baby shower and so I had the kids (almost 4 and 2). Decided it'd be fun to invite my dad out for lunch we we planned on meeting a spot halfway between their place and ours (10 minute drive at most). Got there at the agreed upon time (12 noon) and didn't see my dad outside or in the restaurant. Didn't look too hard, though, thinking that he would have waited outside or in lobby if he had got there earlier. Turns out he got there just after us, waited until 12:10 or so, "poked his head in and didn't see us", and decided to drive to our house to see if we were still there. We weren't, obviously (I was trying to keep 2 kids entertained), and he came back to the restaurant and finally found us (not like we were hiding in a back booth or anything). This, after I had to call my mom (who was at the baby shower too of course) who in turn got concerned that dad got in an accident or something. He backed into a parked car a couple months ago on their street.... so who knows.
But nope, he just didn't think of calling my mom to get my new cell # (not sure why he didn't have it already, but he rarely uses his phone) because she was at the baby shower. Not sure why he didn't peruse the restaurant a bit more knowing that it was past noon and I was kid-wrangling. Anyways, long ### post just to say that pops is probably gonna be dealing with memory issues (and we'll have to be there for him... and will, of course).
GB all those of you dealing with much more troubling issues.