The church records of the New Hanover Lutheran Church, Pennsylvania, contain an entry showing that JACOB CASSEL was born December 6, 1806, and baptized January 13, 1807. Parents are listed as JOHN YUNGLING and MARIA CASSEL. Entry notes Jacob was illegitimate.
I have not been able to connect Jacob or Maria to any other Cassels from that period and locale. If you have information, I would appreciate sharing.