Kate Middleton has gone back to her royal duties after her maternity leave, and she looked radiant as she attended the 2015 Trooping the Colour parade on Saturday, June 13, to celebrate the 89th birthday of the Queen. This marks the duchess' first public appearance since giving birth to Princess Charlotte. 

The 33-year old royal wore a silk, ice blue and white floral Catherine Walker Astrid coat dress, paired with a white Lock & Co's Marisabel hat with curled feathers for the event.

With her were husband Prince William, who donned a scarlet red military dress uniform, and their son Prince George, who is almost two and stole the show by making his first public appearance on a Buckingham Palace balcony. Prince George wore the same blue outfit with lace trim worn by Prince William for his first Trooping the Colour appearance in 1984. 

Other members of the family, including Prince Charles, the Duchess of Cornwall, Prince Harry, and Queen Elizabeth II were present. 

During the parade, the Duchess of Cambridge rode in an Ascot Landau open-air horse-drawn carriage with the Duchess of Cornwall. On horseback were Prince William, who is Colonel of the Irish Guards; Prince Charles, Colonel of the Welsh Guards; and Princess Anne, Colonel of the Blues and Royals. 

Trooping the Colour originated from traditional preparations for battle. Colours, or flags, were trooped down the rank so it could be seen by soldiers. In 1748, it was announced that the parade would also mark the sovereign's birthday. 

Although the Queen's birthday is on April 21, it has long been a tradition to celebrate the Sovereign's birthday publicly on a day in June, when good weather is more likely. The Queen has attended Trooping the Colour every year since 1947. 

The Duchess of Cambridge last appeared in public on May 2, when she and Prince William presented their newborn daughter outside of St. Mary's Hospital hours after Princess Charlotte was born.