My future mother-in-law informed me that the FOG didn't need to rent a tux since she had bought him a nice one a few years ago. I would let that slide, but his tux has a cummerbun and bow tie whereas the rest of the wedding party is wearing a vest and long tie. My father is wearing a black vest. The MOG asked that the FOG be allowed to wear his gold cummerbun to match her dress instead of his black cummerbun. What should I tell her?