The following data is extracted from Genealogy and Biography of Ontario County, New York.
Joshua. son of Edward Clayton, was born about 1735 near Williamsport, Pennsylvania. He was educated in the public schools and learned the trade of millwright. He married, May 16, 1753, Martha, daughter of Aaron and Mary Baker, of West Marlborough, and they came to reside on her father's land. Children: Aaron, born April 2. 1754, married Sarah Bailey; Mary, married Enoch Speakman; Joshua. mentioned elsewhere; Samuel, married Ann Speakman; Hannah, married Amos Speakman: Jacob; Martha; Caleb: Rachel; Susanna and Isaac.
Source: Genealogy and Biography of Ontario County, New York