February 12, 1855, Worcester, Massachusetts.
March 27, 1927.
Worcester Rural Cemetery, Worcester, Massachusetts.
William was the son of William T. and Emily T. Sleeper, and husband of Mabel Allen.
In his earlier years, Sleeper was a missionary to Bulgaria. He was later, for 19 years, pastor of the Congregational church in Wellesley, Massachusetts, and subsequently a worker in the Massachusetts Missionary Society. As of 1923, he was pastor at the Maverick Church in East Boston, Massachusetts. Sleeper’s works include: