Yes. Write. It. Down. Get legal advice and make sure that there are enough copies in secure locations and e-copies as well. Getting it taken care of ahead of time just in case (no one likes to think about it, but it will save so much heartache and time afterwards) for peace of mind. Absolutely, yes, mention it.
(Been through similar situations with family back in Kansas. Not fun.)
@WDEFAustenOnek my parents had everything, including funeral arrangements, done & paid in advance. it makes things SO much easier. i had to deal with my older brother's estate & ugh! that was such a PITA