I'm having a hard time visualizing my fathers attire. I know that often his hanky/tie would match the MOB, however they are not married and he is not remarried. Groomsmen are in Black tux, black vest, purple tie, purple hankie (matches the bridesmaids), FI is in Black tux, ivory vest, ivory tie, ivory hankie. But I don't know what to put my father in... He will be in black tux, but wasn't sure what vest/tie/hankie configuration to put him in. Part of it is that I can't visualize it for some reason part of it is not knowing what is common practice. Thanks in advance.