Buchanan Mcnab

My father Edward James Buchanan, his Father is Clinton Buchanan and Mother was Ruth McNab Buchanan. Grandmother was Margaret remarried to Charles Rolfe. they all lived in Binghamton NY in the 40's on. I think the
Buchanan 's came from Pennsylvania. I remember that dad had and Uncle Jesse Buchanan. And lived on a farm near there. Any information will be helpful.
Edward died in 1992 in Valley Spring SD and Clinton in early 1947. Ruth in the 80's in Binghamton