Sarah Ferguson
The vivacious and spirited redhead married Prince Andrew in July 1986, but she was familiar to the royal family long before becoming the Duchess of York. Sarah and Andrew had known each other since childhood and often played tag as youngsters during polo matches. They reconnected as adults in the '80s after Sarah was invited to Royal Ascot by another of her childhood friends, Princess Diana, who also happened to be Sarah's fourth cousin.
Sarah and Andrew wed at Westminster Abbey nearly five years to the day of Diana's wedding to Prince Charles. They became parents in August 1988 with the birth of Princess Beatrice and again in March 1990 when Eugenie was born. Sarah and Andrew appeared to be drifting apart by the early '90s and announced their separation in March 1992; their split got pretty ugly, especially once photos of Fergie getting her toes sucked by her American financial adviser, John Bryan, were released. It was a major scandal for the royal family, and one that splintered their relationship with Sarah for good. Princess Margaret wrote her a scathing letter, saying, "You have done more to bring shame on the family than could ever have been imagined," and Prince Philip still refuses to be in the same room as her (which explains why he may not attend Eugenie's wedding).
When her divorce was finalized in 1996, Sarah was able to keep her Duchess of York title but was stripped of her HRH styling, just as Diana was. Sarah and Andrew have remained close friends and even continued living together at their family home in Berkshire until 2004. These days, Sarah has a rented apartment in London and a room at Royal Lodge, the former home of the Queen Mother. She also continues much of the charity work she's done since the marriage. Despite their messy past, Eugenie has called her parents "the best divorced couple" she knows.