Who was Kasia Lenhardt?

'Rest in peace! You wonderful, great person, I miss you and I am incredibly sad,' she wrote on Instagram. 'I would have loved to say goodbye to you and can not put into words how much I miss you, I will never forget you! I wish your family a lot of strength. Boateng, who now plays for Bayern Munich, was the first to announce the split after Kasia wrote off his Mini in a crash in Berlin on January 5, with German media reporting that she was over the alcohol limit.