Follow the Heart, Great Exhibition Series by Kaye Dacus and published by B & H Books.
Set during the Industrial Revolution and the Great Exhibition of 1851, Follow the Heart is a "sitting-room romance" with the feel of a Regency-era novel but the fashions and technological advances of the mid-Victorian age. Kate and Christopher Dearing's lives turn upside down when their father loses everything in a railroad land speculation. The siblings are shipped off to their mother's brother in England with one edict: marry money.