Q. Friends and I keep in touch and share our more memorable experiences on Facebook. One friend is an elderly woman who makes comments on our posts that are intended to demonstrate her wit and erudition but which never fail to come across as banal and irritating attempts at point scoring. She is delightful company in person and we have no wish to lose her friendship. How can we encourage her to stop her puerile comments without giving serious offence?
— R.P., London W1

A. Poignantly, your elderly friend may be using Facebook to signal that she still has her wits about her. But, of course, one of the first signs of dementia is that the inhibitory synapses go and long repressed grievances start to be freely expressed. Recruit an exact contemporary to plant a seed of doubt in her mind during real-life chatter. ‘I’ve started running my Facebook comments past my son,’ the fellow oldie can confide. ‘You know the danger at my age is that what I think to be terribly witty can strike the wrong note and be misinterpreted as a sign of the dreaded dementia…’ In this way you should see an end to the nuisance.

Q. Mary, I am hoping you might have some tips for this small problem. I frequently make up reasons why I can’t attend things but then inevitably forget what excuse I gave. I’m not the sort of person who writes things down so please don’t suggest that I do.
— Name and address withheld

A. Give the same excuse each time — that way you can’t forget what you would have said. Try saying: ‘Sadly I’ve got to work that day/night.’ If pressed for details, reply: ‘Don’t ask. It’s so boring.’ If everyone knows you don’t work, then say you’re going to be ‘on a retreat’. If pressed for details say: ‘Don’t ask. It will be so boring. I’m rather dreading it.’

Q. I hope you don’t mind my raising the delicate issue of lavatory cleaning. I would never dream of buying a plastic toothbrush again (we use bamboo now) but there seems to be no ecologically correct equivalent brush for use in a lavatory. I have nine lavatories and I’m afraid we therefore need nine plastic lavatory brushes and nine plastic containers to hide them in. Moreover nine lots are thrown out every few months as they become too repulsive to clean. Unless you have any better suggestions, Mary?
— G.E., Church Stretton, Salop

A. Why not have nine bidet sprayers as used in Asia (where they are known as ‘bum guns’) plumbed in next to your nine lavatories? Forget about using these single hoses for bidet purposes and instead use them purely for cleaning. Have your plumber adjust them so they spurt hot jets rather than warm trickles of water. In this way you need never purchase plastic lavatory brushes or lethal cleaning chemicals again.