Anthony Adolph has produced a pedigree to show her descent from Ed III, this can be seen on <http://anthonyadolph.co.uk/princess-catherine/>.  Supporting articles are in Genealogists Magazine of 2012 and in the same of Dec 2013, vol 4, No. 4, pp. 156.  He also found that Sarah’s life was from 1654 to 1687.

He found Sarah’s parents to be Benjamin Fairfax, a draper of Halesworth, Suffolk and Bridget Stringer.  Benjamin’s parents were another Benjamin and Sarah Galliard and the Fairfaxes continue back to a Sir Thomas of Walton, Yorks who married an Anne Gascoigne, daughter of Sir William Gascoigne and Mary Percy, daughter of Henry the third earl of Northumberland.
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