At Monday’s inauguration of Donald Trump as the 47th president, Barron Trump captured attention with a brief yet enigmatic moment involving Joe Biden. The 18-year-old NYU student, towering at 6-foot-9, leaned down to shake hands with the departing president and whispered something that left Biden visibly serious after initially smiling. The clip of this exchange quickly went viral, sparking widespread curiosity and speculation on social media about what was said….