Mariah Carey’s “childhood dream” will come true when she opens Macy’s Thanksgiving Day Parade. The 52-year-old pop star – who is known for her groundbreaking festive hit ‘All I Want for Christmas is You – took to social media to alert fans that she will be performing at the department store’s annual parade in New York City on Thursday (24.11.22.) She wrote on Instagram: “My childhood dream is coming to life! I’m going to be opening for the one and only, SANTA CLAUS, at this year’s @macys Thanksgiving day parade! Tune in on Thanksgiving Day @NBC.”(sic) Meanwhile, the ‘Always Be My Baby’ hitmake…