Margaret was mentioned in a document presented as the will of Philip Mann, dated 26 Janaury 1818. [Essex County, Virginia, Will Book 19, pages 422–423.]

On 17 November 1823, Peggy Mann, Peter B. Davis and Robert Sowell were bound in the penalty of $4,000 for Peggy Mann’s administration of the estate of Richard Mann, deceased. [Essex County, Virginia, Will Book 19, page 418.]

The estate of Peggy Mann, deceased, in account with A: Brockenbrough, late Sheriff of Essex and committee administrator, from 1824 to 1828 was ordered recorded on 16 June 1828. [Essex County, Virginia, Will Book 21, pages 261–262.]

In the the late 1830s, William G. Mann complained to the Chancery Court in Essex County: Your orator William G. Mann. That his grandfather William Sowell died in ____ intestate leaving a widow Sarah Sowell and two children viz Robert Sowell and Margaret who married Richard Mann. Richard Mann died about 1822 and Margaret died about 1823, leaving your orator and two infant sisters Julia and Margaret Mann. [Essex County, Virginia, Box Chancery No. 39, item 39-L-11.]