Her 4-great grandfather was Garrett Van Sweringen. (8th great-grandfather for my generation)
I just found this really neat biography of him. He was a prominent figure in the early history of St. Mary's City, Maryland and the site of his Inn was the subject of an archeological excavation a couple years back by the St. Mary's Historical Commission. They opened an exhibit on him in April of this year. If I ever get to do a family history roadtrip again I'll definitely be headed to St. Mary's! Read the biography; it's got a lot of neat details from the excavations.
More can be found here, including illustrations created for the exhibit. Click on the link under the Van Sweringen Suite pictures for lots more information.