Me thinks you missed a couple of “Greats.”
My 5th great to be exact. I had said a great grand father without trying to be specific. I grew up with a first cousin twice removed who knew his grandson, she was 104 when she died in the 1970’s. The combination of being very spread out and long lived hasn’t left as many generations as you might think.
There’s a book “The Woodman History of Valley Forge” by his son which although it can be boring presents a great deal of detail about the encampment and some family history.