Mary is my 9G Grandmother. My mom did a lot of research on this line many years ago and I have her research entered into my tree. She listed the source as From "Old Families of Salisbury and Amesbury, MA, MA," by David Hoyt, 1897-1919. It showed that John and Hannah received land in Salisbury, MA, 1640 and moved to Haverhill, MA about 1647 (which puts the family in the right area and general time frame).
But, she notes for Mary that
- Mary Ayer Parker has often been confused with her sister in law Mary Parker who was hanged as a witch during Salem Witch Trial Frenzy and it was probably the Mary Parker who died Sept 1692.
- came from England to Newbury first, then in 1645 at Andover, MA
- oath of allegiance 1678
So, I'd assume that was Nathan's sister that you are asking about. . .
Hope that helped a little :o)