Isabelle, Sebastian's Romani biological mother, defied her community by marrying an outsider. Widowed before Sebastian's birth, she secretly delivered him in the mountains. Leaving him with adoptive grandfather Cecil, she vowed to return when her people accepted their union.

During Sebastian's search for her, Isabelle travels with the Carlos Company gypsy troupe, captivating audiences as their star performer due to her remarkable singing voice and beauty. She also maintains the troupe's costumes, a skill later applied to crafting a wedding dress for Cecil's granddaughter, Anne-Marie.

Her path crosses Mr. Albert, a wealthy admirer who once sent her red roses in Barcelona. Their interactions suggest a developing romance, with mutual acceptance from their respective children, Sebastian and Sarah.

The story concludes with Isabelle permanently reuniting with Sebastian, fulfilling her long-held promise. She abandons her nomadic life to integrate fully into his world.