Your Sarah "Sally' Miller was probably a daughter of Henry Miller and had brother James and Samuel.Samuel took care ofLena and Alphema Wickwire after there parents died.Alphema married George WashingtonMallory and had a son Samuel Miller Mallory, among others.
Theses were the only Millers in the are at that time.
Another clue, Lyman's son Henry M....was Henry Miller Abel...according Ont Gen Society magazine (Families Vol 22-no 1, 1983 "The Abel family and Quakers of Leeds County"
Shirley Hackett is a decendant of Samuel.(She doubted me when I suggested James Miller was related to Samuel, but later found they were brothers.)
Shirley does a great deal of research inOntario.
I am interest inCyrus Abelas his son married a relative of mine in Clarks Merrick Co.He was also Quaker.