But ooooh!
Another marriage at Streatham St Leonard - 29 Oct 1771 (mistranscribed as 1772 on ancestry) - Charles Tristram of Morton in Marsh, coun Gloucs, and Susannah Frost of Streatham, married by licence, witnesses John Frost and Sophia Tristram!
http://search.ancestry.co.uk/iexec?h...c=&pid=4251910
Sophia's signature looks the same as on her marriage.