Calvin, along with several of his siblings, is mentioned in the 1 May 1871 will of his grandfather, Lawton (Layton) Hopkins, of West Greenwich.
In the Federal Census of 1870, Calvin & Catherine Hopkins are living at West Greenwich, RI. They have two young daughters, Lenora 3 & Jennie 1. They are living next to Stephen H. & Angeline F. (Hall) Kettle and their son Leonard W. Hall (Kettle); Leonard later married Abbie Whitford. They are also living next to Sheffield Remington.
In the Federal Census of 1880, Calvin and his second wife Adaline M. are living at Coventry, RI. They have five children in the household.
Calvin & Adaline are both descendants of Simeon Whitford.