Dear Mary: Is there a tactful way to shorten the guest list for my 21st?

Q. I am organising my 21st birthday party at our family house in Italy. It is a fantastic location, but it means that I can only invite about 20 guests. The result of this is that I am unable to invite a group of friends from a university society of which I am a member, despite several of them having invited me to their parties. I will be inviting one person from the group (I knew him away from the society), so the rest will become aware of it. I feel bad for not inviting them, but they are simply not any of my 20 closest friends. Is there anything you would suggest I do to show that I have not ignored them?
— H.G., Plaxtol

A. Ask your parents to plan, but not implement, a ‘themed’ weekend, with activities chosen to be unappealing to the members of your university society. If they are art lovers, for example, a triathlon should do the trick.