You know folks, I always tell my young couples that the day is about making the bride happy, and keeping her Mom from climbing the walls so that the bride can be really happy. I then turn to the groom and say, "You just keep your mouth shut, and at the end of the day you get to take her home." That always gets a nervous laugh from both of them because ultimately there's some truth in it.

Parental disquietude is the biggest stressor for the couple in a wedding. I therefore tell my young couples also, that if there's something they really want or don't want, to check with me and if I can possibly support them, they can then say "Father Bill insists it be that way." The parents can be ticked with me all they want; I don't have to live with them for the rest of their lives.

So... this mom is one that you share with the bride. In my little equation, the question is whether she'll natter at the bride and make her life miserable because of your kilt, ("Your stupid brother..." etc. etc. ad infinitum) or if on the other hand it will deflect any grumpiness from the bride to you. You know your Mom; if she's likely to make an issue over it, choose accordingly. The honourable goal is to make your sister really really carefree and happy on the most important day of her life since she was born.