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In the novel One, Two, Buckle My Shoe, Rebecca Arnholt was the aunt of Julia Olivera, and the wife of Alistair Blunt.

Rebecca's mother was an heiress of the European family of Rothersteins, and her father was the head of the American banking house of Arnholt. Rebecca became the sole heiress of the family's wealth after her two brothers and a cousin died in an air accident.

Rebecca married Prince Felipe di Sanseverato, and they had a child. After three years of marriage, she obtained a divorce and custody of the child. A few years later, the child died.

Rebecca associated herself with her father in banking, and continued to be a powerful figure in finance after his death. She went to London at age forty-five, where she met Alistair Blunt. They were married six months later.

Rebecca's friends had said that she was "an incurable fool where men were concerned", thought that Alistair was marrying her for her money. However, the marriage was a success, to everyone's surprise.

Rebecca passed away after ten years of marriage to Alistair, leaving all her money to him.

It is later revealed that since Alistair hadn’t divorced his first wife, the marriage was invalid.