Found on Genforum:

Looking for info on my Joseph ..birthplace ,parents and (1) wife ....children
Joseph (2) wife was Lydia Stewart m. 23 Feb. 1775 in Shelburne, MA . Joseph and Lydia had one dau. Hannah b. 1776 m. Thomas Rogers.
Any help sure would be appreciated ...

http://genforum.genealogy.com/mckown/messages/232.html

from the findagrave of her husband Joseph:

He married, second, at Shelburne,MA on Feb 23,1775, Lydia Stewart. She was born about 1747, a daughter of Charles Stewart and Mary Ayres Stewart of Colrain,MA. Lydia removed to Ohio in 1812 along with her daughter and son-in-law.

By his first marriage, he had one son who was captured by Indians, taken to Canada, and never heard from again.

Children(by second marriage): Hannah McKeown Rogers.