Woburn records show a Mary Johnson, wife of Capt. Benjamin died 5 Jun 1762. Some genealogies I've found give this date for Mary's death. The Woburn records show that she didn't marry Capt. Johnson until 1765. So the death record must have been for his first wife, Mary Walker.

In 1719 Joseph was engaged to Mary Pierce and they had an illegitimate son (Joseph) 4 mos. later. The record shows no mother's name at the time of his birth. She didn't keep the child with her. She then had another illegitimate child in 1725 and then married that baby's father. Joseph didn't marry until after she married someone else. Was he hoping she would have a change of heart and marry him all that time?

Some genealogies show an Elizabeth Grover as his wife, but there is no Elizabeth Grover in the Woburn records. Some also show another marriage to Mary Grover, too (giving him a total of 4 wives). A Joseph Whittemore, born 1705, married Mary Grover in 1730. They went to Canada.

Thee is confusion about which of his wives were the mothers of which children.