Here's The Most Valuable Member Of The Royal Family, It's Not The Queen 03/12/21 AT 7:38 AM Pictured: Middleton, Princess Charlotte, Prince Harry, Prince George, Prince William and Queen Elizabeth II stand on the balcony of Buckingham Palace to watch a fly-past of aircrafts by the Royal Air Force, in London on June 11, 2016. Photo: Getty Images/Justin Tallis KEY POINTS Prince George and Princess Charlotte could boost the U.K. economy by nearly $10 billion during their lifetime The "Charlotte effect" has brought a huge uplift to brands she has worn or been associated with Her mother Kate Middleton is also known for the "Kate effect"