I read through Samuel BROCKWAY's will, and he mentions his son Timothy, but not Timothy's wife or children.
Samuel does name a grandson, Jesse BROCKWAY. My guess would be that the grandson Jesse was probably a son of Samuel's son, Jesse (also known as Jeremiah). Jesse, the son, died before 11 June 1749, according to research from Walt BROCKWAY and the Wolston BROCKWAY family association. Samuel B. died on 3 January 1775, which happened after his son, Jesse's, death. Therefore, I conclude that Jesse/Jeremiah B. probably a son, Jesse, Junior. I do not have the children's information for that family, but hopefully someone else can verify that "grandson Jesse" was a son of Jesse/Jeremiah BROCKWAY.
There are no other grandchildren mentioned in Samuel's will.