A dog's headstone, with a tile photo of “Bob” and his owner, is seen in an overgrown section of the Aspin Hill Memorial Park in Aspen Hill, Maryland July 22, 2015. Established in 1921, Aspin Hill contains the graves of more than 50,000 animals, from movies stars to WWI heroes to the dogs of former FBI Director J. Edgar Hoover. National Dog Day is celebrated in the United States on August 26. (Photo by Gary Cameron/Reuters)
