I apologize if this is considered off topic on this thread.
This last spring I got an e-mail from a woman who turned out to be an unknown first cousin. Her mother was my father's sister. She married a WWI vet, who probably had PTSD based on descriptions of his behavior. (One of his daughters told the first cousin she could not think of one good thing to say about him.)
The mother died in 1937, and this woman was a baby. So, my dad's brother found a couple to adopt her. She said those adoptive parents rented rooms to university students, and a young man used to come and talk to her a lot, and play with her. She did not understand for years that he was an older brother.
That brother died age 20 on Bougainville, in the Solomon Islands. March 15, 1944, during the final Japanese offense.
She sent a photo someone took of the beach and the funeral tent, with a thing that looked like a surf board, with his name and data on it. He was a Marine which surprised me, because in late 1943, the Marines turned things over to the Army guys. His nickname was "Baby" per the sign.
Recently, I hit a page which said the Third Defense Marine Battallion stayed, so he was clearly with the Third Defense Battallion.
They were told he died from a staph infection, but her bio sister told her she got a letter from a fellow soldier who was with him. They were running for cover when he was killed. The sister now says she cannot find that letter.
His body was most likely buried in the Bougainville cemetery, there are cemetery photos online. After the war, they were moved back home whenever possible.
Those old photos can be fascinating.