Hi Southsea Steel
Thank you for replying to my posting. In Sarah's case, DNA has confirmed who the father of her son was, so I know that he was descended from an English family from Chippenham, Wilts. However, just posting my Chevalier problem has helped me to consider another perspective.
I have been focussed on the lack of weavers in Chevalier line without considering the possibility that the weavers were from one of the Chevalier maternal lines. If this is the case, then the story of weavers in the family may be correct. Sarah's mother Sarah Parkes, bn ca 1788 may well have played in the fields of Rouen if her name had been anglicised from Parques for example, but I have no further information on Sarah Parkes to confirm this. I do know that Sarah's son William spoke French, so there must have been some sort of contact between him & Sarah's family. In any case, none of this explains the lack of DNA from England.
All the best
Chris, NSW, Aust.