I'll be making a post about this soon, but one of my weirder preps is that my partner and I pre-write obituaries for each other annually.
Among many other scenarios that we have planned out, we have put substantial time into ensuring that when one of us passes on, the hard work for the other is done.
It may seem morbid, but my partner and I find it sweet, all the things we get to say about each other. We usually have a cry, a laugh, and get a deeper appreciation of each other when we're done.