As I got to my 60th birthday I found myself looking back at the life of my maternal grandfather who wrote over 600 letters to his wife during his time at the front in the first world war (mainly near Ypres and Somme).
It was so uplifting and I found myself celebrating a great life rather than feeling miserable.
And the University of Southampton has discovered nostalgia is one of the greatest triggers for happiness which relates so well to legacy communications.
Have a look
http://www.theguardian.com/society/2014/nov/09/look-back-in-joy-the-power-of-nostalgia
http://www.theguardian.com/commentisfree/2011/may/04/does-nostalgia-make-you-happy