By Emma Mackenzie Prince William has returned to work for the first time since Kate’s cancer news – and one expert has spotted a small signal the future King has “stepped up” during the tough period. After Kate announced she is being treated for cancer in a moving video message, Prince William paused his royal duties to spend time with his wife and children while George, Charlotte, and Louis were on their Easter holidays. Now they have returned to school for the new term, William has resumed his official duties. With both Kate and King Charles being treated for cancer, it is both a personally …