Apparently Alice married her first husband James' brother Samuel after James died (phone conversation between Edward A. Dunscombe and Philip B. Stewart, 6 Sabal Ct., Sewall's Pt., Stuart, Fl., about 1990).
We catch the last glimpse of Alice, apparently then a widow, "living at Merrimans" (probably the family of a daughter) and evidently soon to move with that family still westward "to the Ohio." It is supposed that she died in or near Beaver, Pa. She is said to have been called a "whole divine," good Scotch doubtless in theology. A Spartan mother who gave to her offspring their full share of the ancestral love for emigration, and to her sons that stanch and fearless patriotism that flowed so naturally in her veins
(Severance, B. Frank. Genealogy and biography of the descendants of Walter Stewart of Scotland and of John Stewart who came to America in 1718 and settled in Londonderry, N.H. Greenfield, Mass. : T. Morey & Son, 1905, pg. 28).