The Wallflower Brides Club Series by Jayne Rivers, Maggie Kent

A taciturn duke. A smitten wallflower. A secret that could ruin everything. If Lady Charlotte Fitzgerald does not wed this season, she risks being declared a spinster--or worse, being forced into a betrothal with the most unpleasant cad in the ton. Unfortunately, the only man she wishes to marry--the surly but kind-hearted Duke of Arundel--only sees her as a younger sister... moreA taciturn duke. A smitten wallflower. A secret that could ruin everything. If Lady Charlotte Fitzgerald does not wed this season, she risks being declared a spinster--or worse, being forced into a betrothal with the most unpleasant cad in the ton. Unfortunately, the only man she wishes to marry--the surly but kind-hearted Duke of Arundel--only sees her as a younger sister. When she, the duke, and her closest friends are invited to the same house party, it's the perfect opportunity to win him over--if only he weren't so skilled at avoiding her. Lady Charlotte is prepared to risk everything for the man she adores, but her gruff duke is keeping a massive secret, and if it comes to light then her dreams for the future will go up in flames. less