Years ago I came across someone(a Kuzio or a Jones?) trying to place this child from Pa. Mary did not fit into my established Leonhardt (Pa) line from 1730. Later, I came across my Leonhardt being established the administrator for his younger brother's estate. Papers show brother Philip was in the 2nd Pa. army when he died in 1760. I have found followup papers which show the inventory went through the Orphan's Court by 1761.
Since Martin's line went to Maryland and Kublingers were later, and in the south, I am thinking this Mary may have been a posthumous child of Philip, brother of my Leonhardt Keplinger. But I have no other information.