Jackie Hooper is a writer who is putting together an anthology called The Things You Would Have Said. It is full of letters from individuals who never got the chance to tell people in life/in person what they wish they would have. (I think if you go to her site you can read about how you can submit your own letter.)
Months ago Jackie asked me to submit something to her collection, and I did. Eventually, it'll appear in book form, but she let me know that yesterday it was featured on her site.
So, check it out. It is to my grandmother who is still living but with dementia. I wrote about this a few months ago, but was not allowed to post the exact letter I'd submitted to the anthology. But now you can actually read the original on her site.
I wonder how my letter would be different if I had written it today, with the knowledge that my grandfather is no longer alive. He died in October.