A blind schoolgirl with a large brain tumour sang a Christmas song and gave the Queen a handmade ring when she was invited to Windsor Castle for tea.Olivia Taylor, who has been blind since not long after her diagnosis aged 17 months, shouted “hello Your Majesty” while jumping with excitement when Camilla walked into the White Drawing Room for a private tea with her family.The seven-year-old also tried her very first cup of tea, which was poured by the Queen – and after a long sip she said “I love tea”. "You’ll be able to have tea from now on,” Camilla replied.