Time is really flying, and Prince George and Princess Charlotte are growing up so fast, while they helped their mom and dad at Heathrow Airport on Thursday October 21. Prince William and Kate Middleton‘s 8-year-old-son and 6-year-old daughter were standing on the sidewalk at the airport entrance with their backpacks in tow, along with their younger brother Prince Louis, 3, via DailyMail. Check out the photos HERE!