When my father was dying, shortly before one Christmas, he was upset that he couldn’t get out to buy my mother a present.
So she said ‘Write me a letter,’ which he did. He was a v good letter writer - for years she’d kept all the letters he’d written her during WW2 and was very upset when they were lost during a move.
For ages after he died she kept that last letter under her pillow. Sadly, though, it later went missing - evidently thrown out with sundry other stuff after she succumbed to dementia.?
Mind you the dementia did at least erase her former grief. When she was mid-stage and I showed her a photo of him, she just said very vaguely, ‘Oh, yes, did he die?’ Not upset or bothered at all.