Prince William walked the green carpet Tuesday alongside stars including Cate Blanchett, Sterling K. Brown and Hannah Waddingham at the awards ceremony for his annual Earthshot Prize. William attended the ceremony in Singapore without his wife Kate, the Princess of Wales, who did not attend the event for a very personal family reason. According to the Prince of Wales, Kate, who shares three children with William, stayed home in the United Kingdom to help their eldest child Prince George prepare for his school exams.