I have only ever seen one memento mori photo in real life (found at a yard sale) and i was enthralled.
These photos were taken by a photographer who specialised in these types of images, and often advertised under the banner of "Post mortem Photographer"
Photography became more affordable during the middle 1800's & although more families could afford the high fee's they were still, however, a huge financial sacrifice for most.
The majority of folk back then did not have access to a camera let alone a photographer so when a loved one died they would hire the services of this special photographer, often calling for them when a loved one was close to death, so as to have a permanent reminder of their dear departed loved ones.
During the second half of the 1800's the infant mortality rate was very high, and many babies and small children would die before a photo could be taken of them, also many young women died during childbirth and disease was known to take whole families.
Sometimes these photo's would have the subjects eye's open,
depict mother and child, (one or the other or both departed)siblings, sometimes only the face would be captured, they could be laying down looking like they were asleep or sitting up in a rocking chair.
If you are reading this Lula or Hud i suggest you start saving now for my very own
momento mori photo,and no, i don't think you can take me to Walmart to have it taken either.
One website i like http://www.thanatos.net/