Immortelles by Lynn Morris

For her sixteenth birthday, Damita De Salvado receives a beautiful slave girl, Rissa, but mistreats her, revealing Damita's prejudice and hardening Rissa's heart. When her family experiences financial hardships, Damita grudgingly sells Rissa to a mysterious Christian doctor, Jefferson Whitman, who is Rissa's adopted brother. Now the tables have turned: Rissa is a wealthy, free woman, while Damita's family struggles to keep the plantation. Will both women find the love and security they long for?