My mother-in-law takes pride in keeping a cold house. How can I politely ask her to light a fire or buy an electric heater? I don’t want my children to freeze.

A. M., Perth

Blustery Boreas, king of the frozen North! Wrap your fragile little darlings in vests, jerseys and leg warmers before you visit Mother. We all have different metabolisms, and different tolerances of hot and cold. Up in your Highlands you have a tradition of log fires (usually hogged by the bottoms of the males). There is an old Latin saying: Alget qui non ardet — she freezes who does not burn. Down here in the soft South, excessive heat in public transport and private flats is more of a problem than cold. We should dress for the climate. And we should be wary about crossing our mother-in-law over the way in which she prides herself on running her house. It should also be possible to refer in a joky, not a carping, way to the chill in your mother-in-law’s home. Cold hands, warm heart.

What is your opinion of Christmas cards?

Peter Dunne, Tooting

A bonanza for the stationers. An annual opportunity to catch up with one’s neglected friendships. A faint reminder of the meaning of Christmas, and the foundation of British civilisation. Their origin is odd. Christmas cards emerged in the mid-19th century, combining an older custom of sending new year verses to friends with the new emphasis on Christmas. The first Christmas card was designed in 1843. A large central panel shows a family sitting with wine glasses in their hands, and a banner saying: “A Merry Christmas and a Happy New Year to You.” Two side panels show a man and a woman giving alms to the poor. The idea spread. By the 1860s cheap cards were generally available. Religious symbolism is strikingly absent. Family gatherings, dancing, winter scenes, stage coaches, holly, Christmas trees and robins were the standard fare. They still are. Two good rules are to support charity cards, and to avoid all attempts at jokes or rudery.

Is there any way I can persuade my grandchildren to write thank-you letters?

Harriet R., London

By love and good example. Letter-writing is an almost obsolete art form. A pity. There are various cunning ploys. For example, sending a letter announcing that it encloses a cheque/ postal order/ tenner to your grandchild, and omitting to enclose the dosh. She or he will then feel bound to reply, pointing out your omission. But I prefer to explain to the little darlings, gently, that you like to hear from them, because you are interested in their careers, and are cheering for them from the touchline. They text or e-mail or mobile rather than write. This does not mean that they are any less faithful or grateful than we were.

My father is an elderly housebound 87-year-old. One of his sons shops for him and delivers his groceries each week. He uses my father’s credit card. According to some of the statements, my brother has been using the card for his own shopping and petrol as well. How can I raise the matter with my brother without causing a row?

Anonymoses, Plymouth

Am I my brother’s keeper? No. But I ought to be his dear friend. Why are we snooping? We need all the brothers we can get in this wicked world. We must, at all costs, avoid a family feud over something as trivial as money. Easy enough to say, when one has just about enough to pay for the groceries. But, in the long vista of life, money is trivial as well as vulgar. Not worth falling out with a brother over.

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