Donald Trump’s spokesperson made it clear that he didn’t blow off his 10-year-old grandson, Joseph, when he was seen mingling with celebrities and Ivanka Trump and Jared Kushner at the UFC match in Miami on March 9. “Trump blew off his own grandson while he was mugging with B List celebrities and the kid was pretty bummed out,” attorney Ron Filipkowski wrote via X, formerly known as Twitter, alongside the video clip. “This is who he really is behind the fake show.” Steven Cheung, Trump’s campaign communications director, clapped back at the accusations, stating: “Imagine being some sad, baseme…