Male child born 17 Aug 1705 (source below) precludes the birthdate of Margaret Summers. This needs to be researched further.
Thomas Summers may have later married Elizabeth Perry, 05 Jun 1709 in Saint Peter's Parish, Talbot, Maryland.
"Maryland Births and Christenings, 1650-1995," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:F4ZQ-F49 : 11 February 2018), Thomas Summers in entry for Summers, 17 Aug 1705; citing Somerset, Maryland; FHL microfilm 14,361. (shows wife "Bridgett" "Demsey" and husband Thomas Summers)
It may be possible to confirm family relationships with Bridget by comparing test results with other carriers of her mitochondrial DNA.
However, there are no known mtDNA test-takers in her direct maternal line.
It is likely that these autosomal DNA test-takers will share DNA with Bridget: