An enemies-to-lovers romance. When they were children, Ellen Laughton considered the Duke of Castlefield her best friend. But when he learned their parents were hoping they'd marry one day, he did what any boy of twelve would do—he pushed her away. She’s been angry with him ever since. By the time Castlefield realized there was only one woman for him, Ellen was already betrothed to another. Now that she’s a widow and out of mourning, he is determined to win back her friendship and her heart. But when Ellen learns about the role he played in her husband’s death, will she be able to forgive Castlefield’s betrayal? THE UNSUITABLE DUKE is a Regency Historical Romance is book 4 in the Landing a Lord series. It contains the themes of enemies to lovers, widow, childhood friends, second chances. 238 print pages.