FASHION designer Lloyd Klein is meeting his 20-year-old son, Mathias, on Father’s Day – for the very first time. A few months back, Klein got the shock of his life when he was contacted by Mathias, who lives in Basel, Switzerland. The young man explained that his mom – a top European model Klein dated in the ’80s – had just informed him that Klein was his father. The duo plan to meet at the Beverly Hills home of Klein – who’s dressed Tyra Banks, Jessica Simpson and Eva Longoria – and play catch-up.