See this G2G discussion about alternative claims that she was also the spouse of Nicholas Jacob and John Beale in Hingham.
What's now clear is that two Mary Gilmans emigrated to Massachusetts:
Mary Gilman, b abt 1600; m abt 1625 Nicholas Jacob; emigrated with him in 1633 and settled in Hingham; after Nicholas died she m2 John Beale. She died in 1681. She was the sister of the emigrating Edward Gilman.
Mary Gilman, bpt 1615 in Hingham, Norfolk, England, daughter of Edward Gilman, the immigrant. She married in Hingham in 1636 John Folsom, emigrated with him and her parents in 1638, settled initially in Hingham, then they all went to Exeter, NH; she died in 1691.
She was christened 6 August 1615 in Hingham, Norfolk, England
She, along with her husband and her parents, departed from Gravesend, Kent England on Gravesend, Kent, England, arriving Boston, MA 10 August 1638
According to the Genealogical Dictionary of Maine and New Hampshire, husband John Folsom died in 1681, and Mary was still alive.
[the following needs examination. IF the following is Edward the immigrant, it should remain here as he is Gilman-115's brother, not father.]
↑Genealogical Dictionary of Maine and New Hampshire [Ancestry.com. database on-line]. Provo, UT, USA: Ancestry.com Operations Inc, 1998. Original data: Libby, Charles Thornton. Genealogical Dictionary of Maine and New Hampshire. Portland, ME, USA: The Southward Press, 1928. Page 237
Find A Grave, database and images (https://www.findagrave.com : accessed 19 March 2019), memorial page for Mary Gilman Foulsham (6 Aug 1615–1692), Find A Grave: Memorial #27512902, citing Congregational Church Burial Ground, Exeter, Rockingham County, New Hampshire, USA ; Maintained by Lori Rowe (contributor 46922820) .
It may be possible to confirm family relationships with Mary by comparing test results with other carriers of her mitochondrial DNA.
Mitochondrial DNA test-takers in the direct maternal line:
Frank Gill :
Mitochondrial DNA Test HVR1, haplogroup H