WINDSOR, ENGLAND - MAY 15: Zara Tindall rides out on the final night of Queen Elizabeth II's 90th Birthday Celebrations at Windsor on May 15, 2016 in Windsor, England. (Photo by Chris Jackson/Getty Images)
WINDSOR, ENGLAND - MAY 15: Zara Tindall rides out on the final night of Queen Elizabeth II's 90th Birthday Celebrations at Windsor on May 15, 2016 in Windsor, England. (Photo by Chris Jackson/Getty Images)