I am not sure, but I think Thomas must have been the brother of George Abbot, who was the immigrant ancestor of our branch of the Abbot family.George was born in 1615 in County Herts, England, and came to Andover, MA in 1640.He was the son of George and Elizabeth Abbot of Bishops-Stortford, Co Herts, England.He was one of the first settlers of Andover, MA.He was a property owner in 1643 and his name is on the list of householders written in the order in which they came to town.His house was used as the garrison.The farm descended to at least eight generations of the family.He died at Andover, Dec. 24, 1681.His will dated Dec. 12, 1681, proved March 28, 1682, bequeathed to his wife Hannah, eldest son, John, other children to inherit at the death of his wife.HIS BROTHER, THOMAS AND WILLIAM CHANDLER WERE OVERSEERS. George married at Roxbury, MA on Dec. 12, 1646 to Hannah, daughter of William and Annis Chandler.She married 2nd as his third wife, Reverend Francis Dane.Hannah died at 82 on June 11, 1711. This is from, "A Genealogical Register of the Descendantsof George Abbot of Andover." It was compiled by Rev. Abiel Abbot, D.D. and Rev. Ephriam Abbot, 1847.
I could not find a Sarah Stewart in our book, but I did find the name Sarah used as the seventh child of George and Hannah.
Hope this helps you.Would like to know if they were really brothers or not. Sherry