sentences:  The following biography is therefore tentative and incomplete, deduced from a comparison of published local and family histories, clues left by Eliza in her own writings, and a search of parish records and census data.Although Mary Shelley's biographer, Emily W. Sunstein, claims that Eliza was born to the famous engineering family Rennie, of John Rennie the Elder and his sons George and John, no corroborating evidence has been found.One possible matching birth record between 1805 and 1820 has been found of an Elizabeth Rennie born on 17 May 1813 to Alexander Rennie and Jean Taylor in the village of Udny, Aberdeenshire.