Flowers from the Storm. I've read most of her books, and this one is my favorite. Kinsale was one of the first romance authors to write about deeply damaged heroes, and she remains the best, in my opinion.
The hero, Christian, is a rakish duke who is also a mathematical genius. Over the years he has formed a friendship with a fellow mathematician who is a devout Quaker. His friend's daughter, Maddie (short for Archimedea), is thoroughly disapproving of the promiscuous duke but shows him the respect due to her father's friend.
Early in the book, Christian suffers a cerebral hemorrhage. Like many stroke victims, he is partially paralyzed at first, and his speech is severely compromised. His family sends him to an asylum, where he is treated every bit as badly as one would expect in that time and place, despite his aristocratic title. As Christian slowly begins to recover, he realizes that his relatives want to keep him locked up, so they can control the ducal property.
He manages to escape and find refuge with Maddie and her father. The only way he can wrest legal control back from his grasping relatives is to make Maddie his next of kin by marrying her, then recover sufficiently to convince the authorities that he is of sound mind, so the marriage cannot be put aside. The story involves his efforts to convince her and the difficulties in bridging the gap between their worlds, made all the more difficult by his struggles to find and form words. Their differences were many, but Kinsale made me believe in their ability to love each other and find ways to compromise.
This book was ahead of its time in so many ways. In addition to the realistic portrayal of Christian's brain injury, Maddie's Quaker religion is not just an opposites-attract plot point. Her faith and moral beliefs are central to who she is as a person. When her husband seduces her, she realizes that she desperately wants him but also feels guilty for those desires, because she suspects her reasons for marrying him were not purely altruistic. She is angry when he hosts a lavish ball, spending freely on luxurious food and decorations, when so many Londoners are starving and homeless.
I periodically re-read this book, when the details have faded sufficiently from my memory that the scenes and dialogue once again feel fresh. I consider it one of the best romance novels ever written.
Only Enchanting, the latest in her Survivor's Club series, which are all about wounded veterans of the Peninsular War. The hero of the latest installment is Flavian, a viscount who suffered a traumatic brain injury in battle. Years later, he is mostly recovered, although he still speaks with a stammer and occasionally suffers from mild aphasia. He also has gaps in his memory that frustrate him. He briefly meets the heroine, Agnes, at a friend's party and finds her only mildly attractive but somehow memorable.
When it becomes clear that his family has plans to reunite him with his former fiancée, he finds the idea repugnant but cannot quite remember what it is about her that bothers him so much. He courts Agnes and convinces her to marry him because he feels like he will be safe with her (although he is not sure what need he has for safety).
The story is well-written, and I enjoyed it. I could not help comparing it to Flowers from the Storm, though, and that is a very high bar. Both books have a brain-damaged, rakish hero with aphasia who pressures a reluctant woman into marriage to shield him from the manipulations of his relatives. The stakes are far lower in Only Enchanting, since Flavian does not face being committed to an asylum.
Balogh has been writing about wounded veterans of the Napoleonic Wars for a number of years, even before her Survivor's Club series. The reading public's interest in such stories has undoubtedly been influenced by the large number of wounded veterans who have come home from the conflicts in Iraq and Afghanistan. There are some contemporary romances published in recent years with military veteran heroes who have suffered traumatic brain injuries, and it is unsurprising that Regency-set historicals are also focusing more on the fall-out from that era's lengthy and brutal overseas conflicts.
I can recommend both books as good reads. If you plan to read both of them, however, I recommend that you read Only Enchanting first, and let it serve as the opening act.