So John Leslie McFatter is a "stray" McFatter who seemingly does not fit into any of the known McFatter/McPhatter families. We have marriage records, some later census records, his death certificate, his social security application, all sorts of documentation, except that which will solve his filiation.
He was born in 1877 in Montgomery co. MS, so would seemingly belong to the branch descended from Niven McFatter which populated the Attala-Webster-Montgomery-Carroll counties area. However, he does not appear on the 1880 census, at least not that I can find. He enlists in the army in 1904 in Kansas City, MO. Then he moves north to NY, marries, is living variously in NY and VA, and then dies in Virginia in 1945.
His death certificate lists his father as John McFatter, and his SS application says his parents are Jonathan E. McFatter and Mary J. McCarroll, and that he was born in Montgomery co. MS. That's all well and good, except I can find no proof these people existed. In 1877, the only McFatters from MS named John were John Niven McFatter, aged about 19, who may have already been in Texas by then; a younger John Niven McFatter who was aged 1 year; and my own great-grandpa John Adams McFatter, who was about 8 years old. The only one who could possibly be John Leslie's father is the elder John Niven, and if he's the father, it seems John Leslie would either have had to be born out of wedlock, or the mother died very, very young. If the mother died young, it seems John Niven must've abandoned him as he left for Texas and by all accounts never returned to MS or had anything to do with anyone back home.
There's no John or Jonathan E. McFatter of the right age anywhere, much less married to a Mary J. McCarroll. This is very confusing!