yacht Britannia for a sailing weekend to Cowes. This was followed by an invitation to Balmoral Castle (the royal family's Scottish residence) to meet his family. She was well received by the Queen, the Queen Mother and the Duke of Edinburgh. Charles subsequently courted Diana in London. He proposed on 6 February 1981 at Windsor Castle, and she accepted, but their engagement was kept secret for two and a half weeks. Engagement and wedding Their engagement became official on 24 February 1981. Diana selected her own engagement ring. Following the engagement, she left her occupation as a nursery teacher's assistant and lived for a short period at Clarence House, which was the home of the Queen Mother. She then lived at Buckingham Palace until the wedding, where, according to biographer Ingrid Seward, her life was incredibly lonely. Diana was the first Englishwoman to marry the first in line to the throne since Anne Hyde married the future James II over 300 years earlier, and she was also the first royal bride to have a paying job before her engagement. She made her first public appearance with Prince Charles in a charity ball in March 1981 at Goldsmiths' Hall, where she met Grace, Princess of Monaco. Twenty-year-old Diana became the Princess of Wales when she married Charles on 29 July 1981. The wedding was held at St Paul's Cathedral, which offered more seating than Westminster Abbey, a church that was generally used for royal nuptials. The service was widely described as a "fairytale wedding" and was watched by a global television audience of 750million people while 600,000 spectators lined the streets to catch a glimpse of the couple en route to the ceremony. At the altar, Diana inadvertently reversed the order of his first two names, saying "Philip Charles" Arthur George instead. She did not say she would "obey" him; that traditional vow was left out at the couple's request, which caused some comment at the time. Diana wore a dress valued at £9,000 () with a 25-foot (7.62-metre) train. After she became Princess of Wales, Diana automatically acquired rank as the third-highest female in the British order of precedence (after the Queen and the Queen Mother), and was fifth or sixth in the orders of precedence of her other realms, following the Queen, the relevant viceroy, the Duke of Edinburgh, the Queen Mother, and the Prince of Wales. Within a