Re: Marcus/Marx Schwenk, Schuylkill 1780
For Lydia, I'd just look for that. Also spelled Lythia.But it's not commonly a nickname for something else, at least not at that time.
If you tried the easy ones, you might want to check the courthouse in Reading.Lydia is probably from one of the families that stayed in the area.Don't forget to look under
Schwenk, Swenk, Swank, etc.Also look for deeds that settled the estates when there was no will.
Post if you find a connection.I can email the details I have on the first couple generations.