I have been able to trace a Mcelroy descendent as far as John A. McElroy who died in 1845 in Allegheny County. He left 2 minor sons, Thomas and Matthew. Matthew grew up on a farm with a family named Gwinn. Matthew's birth certificate indicates that his mother's maiden name was Shearer. Can anyone tell me the best way to get past this wall? Or do these names sound familiar to anyone else? Thanks so much for any help at all.