Jacob Griswold, 1734-1768, wives Susannah and Mercy

Jacob Griswold, 1734-1768 married Susannah Bowen first. Does anyone know her parents?She died young, but may have had a son, Moses.

However, Jacob's will refers to wife " Mercy."Does anyone know anything about her?

There were two sons, Jacob and Josiah.Descent is through this Josiah and wife Abigail C. Wells.This family is said to be mixed up for several generations in "History of Ancient Wethersfield."
I have tried for years to find the answers and would be so happy if there were a breakthrough out there!