Jack of Hearts by Candace C. Bowen
Approx. 83,760 words.
Published on March 21, 2013 by
Seven Realms Publishing.
During the height of the Whitechapel Murders, Katherine Kelly teams up with Constable Edward Stanhope to search for her older sister, Mary. They soon discover the closer they come to finding Mary, the closer they come to finding Jack the Ripper.