Born in Burslem, Staffordshire, the eleventh and last child of potter Thomas Wedgwood (d. 1739) and Mary Wedgwood ("née" Stringer; d. 1766), Josiah was raised within a family of English Dissenters; he was the grandson of a Unitarian minister and was an active Unitarian. By the age of nine, he was proving himself to be a skilled potter. He survived a childhood bout of smallpox to serve as an apprentice potter under his eldest brother Thomas Wedgwood IV. Smallpox left Josiah with a permanently weakened knee, which made him unable to work the foot pedal of a potter's wheel. As a result, he concentrated from an early age on designing pottery and then making it with the input of other potters. The pottery created in his father's and brother's business was inexpensive and low quality, black and mottled in color.