 During their time in Cincinnati, Nicholas displayed an irrational jealousy that later fueled Caroline's Byronic heroes.“According to their son, Dr. Charles A. Hentz, Colonel King of the Semi-Colon Club, sent an improper note to the dignified and accomplished Mrs. Hentz.” When she attempted to respond to the note, her suspicious husband discovered the correspondence.After threatening to duel Colonel King, Nicholas swiftly closed down the school and the couple moved to Florence, Alabama, where they opened another school.