On the marriage to her first husband, the 17th Baron Hastings, it was not well received as Frances was not from the same social hieracy, and on the death of her husband he left her a large legacy which apparently was contested by the Astley family when her late husbands brother became the 18th Baron Hastings.

While they did not have children, Frances and the 17th Baron took on their nephew, William Thomas Cosham and sent him to Eton, where the Astley family had always schooled. At the age of 18 William Thomas Cosham changed his name to Hastings.