Hi Jeff,
I don't believe there is a will, but in the land transactions of the State Archives, there is a document transferring land belonging to the heirs of George Hoppock, which includes the names of his four children: Elizabeth, Catherine, Peter and Mary and their spouses.

There is also a letter in the Hunterdon County Historical Society from Peter's granddaughter to Hiram Deats, where she refers to her grandfather's sisters, Elizabeth Hamilton, Katie Stevenson and Polly Manning.

Hope this helps,
Chris