Michael Jordan 's son Marcus Jordan 's summer is heating up nicely ... because he was spotted strolling hand-in-hand with a mystery brunette during a flirty day on South Beach. The two looked plenty comfortable together Sunday as they soaked up the South Florida sun ... with Marcus rocking an all-black outfit while his companion turned heads in a red bikini top, striped shorts and a cheeky look that had beachgoers doing double takes. They stayed close throughout the outing, chatting as they