She married the marquess in London on 9 May 1839, more than thirty years before he inherited the title from his cousin, Richard Seymour-Conway, 4th Marquess of Hertford, who died without direct heirs. The couple had ten children:
Frederica Georgina Seymour (1840–1848), who died in childhood
Lady Horatia Elizabeth Seymour (1842–1922), who married Sir David Erskine, a direct descendant of the Earls of Mar and had children
Reverend Lord Victor Alexander Seymour (1859–1935), who married Elizabeth Cator and had children
The marquess died in 1884, aged 71, as a result of a fall from a horse at the family home of Ragley Hall in Warwickshire.[2] He was succeeded in the marquessate by his eldest son, and his widow became known as Dowager Marchioness of Hertford. She died at Brooklands Manor, Westcott, Surrey, aged 86.[3]