BETHESDA, Maryland — First lady Melania Trump on Wednesday encouraged a group of sick teens to be candid with her — with one Romeo capitalizing on the green light. “I don’t play chess but I know a queen when I see one,” said the smitten young man with glasses, joking he’d like to call President Trump’s wife, her “highness.” The first lady, 55, flashed a big smile. She called the flirty cupid a “charmer” and joked that girls need to “watch out.” The heart-warming exchange came at The Children’s