On 21 Jan 1800 when Otis was 30, he married Dorothy Perkins in Castine, Hancock County, Maine. Born on 17 Jun 1779 in Castine, Hancock County, Maine. Dorothy died in Castine, Hancock County, Maine, on 3 Nov 1856; she was 77.

Dorothy, daughter of Joseph and Phebe (Weare) Perkins.