In the novel The Rose and the Yew Tree, Adelaide St. Loo (The Dowager Lady St. Loo) is the widow of the seventh Baron. The couple had two sons. Lady St. Loo's husband had died in the Boer War and both her sons had died in the Great War.
Lady St. Loo is the sister of Lady Tressilian and the sister-in-law of Mrs Bigham Charteris. She is also the grandmother of Isabella Charteris.