Take a look back at the royal romance of Prince William and Catherine, the Duchess of Cambridge.
2001: Kate Middleton meets Prince William at the University of St. Andrews.
2003: Prince William and Middleton begin dating around Christmas.
October 2010: Middleton and Prince William become engaged during a trip to Kenya. Prince Charles officially announces the engagement on Nov. 16, 2010.
Dec. 18, 2010: Middleton and Prince William make their first public outing after announcing their engagement.
April 29, 2011: Prince William marries Middleton, who becomes Her Royal Highness the Duchess of Cambridge, at Westminster Abbey.
June 30-July 8, 2011: Prince William and the Duchess of Cambridge take their first official trip to a foreign country, Canada.
July 8-10, 2011: The Duke and Duchess of Cambridge are in Los Angeles for a three-day visit where they visit Hollywood, Skid Row and veterans. It is Catherine's first trip to the United States.
Sept. 11, 2012: Prince William and the Duchess of Cambridge look at orchid hybrids named in their honor at the National Orchid Garden in the Singapore Botanic Gardens. The garden was the first stop for the royal couple, who were on a three-day tour of the city-state as part of a tour to mark Queen Elizabeth II's Diamond Jubilee.
Sept. 15, 2012: Prince William and the Duchess of Cambridge cross a bridge at the Borneo Rainforest Research Center in Danum Valley, some 43 miles west of Lahad Datu, on the island of Borneo. The royal couple were on their second stop of a nine-day tour of Southeast Asia and the South Pacific on behalf of Queen Elizabeth II to commemorate her Diamond Jubilee.
Dec. 6, 2012: Prince William and the Duchess of Cambridge leave King Edward VII Hospital, where she was hospitalized with acute morning sickness. Catherine's four-day hospital stay led the Royal Family to announce on Dec. 3 that she was pregnant with the couple's first child.
June 15, 2013: The Duchess of Cambridge and Prince William stand on the balcony of Buckingham Palace after the Trooping the Color ceremony in central London. Catherine's appearance at the ceremony is her last public appearance before giving birth.
July 22, 2013: Prince William and the Duchess of Cambridge welcome their first child, a son.
July 23, 2013: Prince William and the Duchess of Cambridge introduce their new baby boy to the world. The next day, they announced the baby's name: George Alexander Louis.
April 2014: Prince William and Catherine take Prince George to New Zealand and Australia, his first official tour.
Sept. 8, 2014: Buckingham Palace announces the royal couple is expecting their second child.
Can't get enough of Prince William and Kate? Click here for more on their son, Prince George.