Johan Adam George 1732 1806

Trying to establish a connection to Johan George of Franklin, Pa through my grandmother Sophia George Salsbury Kehl (1802-). She's supposed to be the daughter of John George (1765-) and John is Johan's son. The only link I've found so far is a dead message board post claiming to have documents that show Sophia is John's daughter. Johan would be my first Revolutionary soldier on my maternal side.