He's #9 in the chart
https://books.google.com/books?id=5ikwAAAAYAAJ&pg=PA202
Looks like a rather obscure person. But there seems to be a difference of opinion about who his mother was.
https://archive.org/stream/visitationscoun00vincgoog#page/n73/
has Margaret St Mark erased on the manuscript, but stuff like that doesn't bother the internet.
But she's in this rambling Steward pedigree as well
https://archive.org/stream/visitationsnort00vincgoog#page/n210/
though I doubt if all this was given in evidence by John Steward.
