Started by spiderman123 on NeoGaf.com
Can't Put your Kid to Sleep…Amazon has your answer!

It was ment to be a link for a comedy book that was for adults as well as kids. Then someone noticed a book that was called "All my friends are dead". From that point on, everyone got on board with the photo-shopping. It is still a very new meme, but a hilarious one at best.

The sight of the sad dinosaur prompted mix ins with various other meme's and topics.

Source:

http://www.neogaf.com/forum/showthread.php?t=430658