"Erastus's father Isaac is mentioned in the Abbot genealogy here, and his mother Susan is mentioned in the Ela genealogy here. This should help you start tracing the lines back, though you'll have to confirm the information through your own…"
"You asked "any way to track that down"
Yes, there is - continue to research your family one generation at a time working your way back until you find your answer or run out of places to look for family documents.
"According to the records of Franklin Plantation, Julia Jennett Abbott was born 3 April 1864, the daughter of Erastus J. Abbott and Lydia Ann Ackley.
Erastus was born 28 Jan. 1818 in Hartland, Windsor County, Vermont; Lydia was born 28 April 1823,…"