For many happy pre-school years we got away with a drawing, a wobbly signature and a dictated letter penned by myself. Now thank you letters can stretch into the beginning of term; that first flurry of activity armed with an arsenal of glitter pens and new letter writing kit waning to one laborious sentence a day. Even more painfully, my children are now at an age where phonetic spelling ('Fanks for the jiksaw') has slipped from being funny to frankly worrying.
'Why bother?' says one friend and godmother, who's declared an amnesty on children having to write thank you letters. 'Just pick up the phone. Anyway, if your children do it, mine will have to, and life's just too short.'
But for grandparents and distant relatives, I still believe my potential pain is worth their pleasure at receiving a thank you letter.
After my grandmother died, we discovered she had kept a drawer full of thank you letters from her 13 grandchildren. Some were terse two liners, some ebullient descriptions of family Christmases, and all obviously much treasured, even decades later.
'A little appreciation goes a long way,' agrees etiquette expert Jo Bryant, editor of Debrett's Correct Form. 'As soon as children are old enough, they should be encouraged to write thank you letters. Nothing beats a nice hand-written letter saying thank you, with a little bit of padding as to why the present was special or what they're going to do with it and a piece of news. Make sure it sounds sincere, not too flowery or false, and make an effort to write on good quality plain paper with a nice pen, not a biro. We recommend you should send letters by first class, within a week to 10 days after Christmas. If you're really behind, you could make a holding phone call but do still write the letter.
And honesty is not the best policy when writing thank you letters. The recipient does not want to know you'll be swapping it for something more to your taste, already have one or have broken it, lost it or can't remember what it was. My sister perfected the art of thanking a great aunt for the colouring books she was still receiving into her teens. At the end of the bread and butter letter she would sign it with her age in brackets.
But the best 'no thank you' letter goes to family favourite, Horrid Henry. Infuriated by his parents' insistence on writing five sentences to thank his Aunt Ruby for a revolting lime green cardigan, he writes: 'No thank you for the horrible present. It's the worst present I have ever had. Anyway, didn't some old Roman say it was better to give than to receive? So in fact, you should be writing me a thank you letter. PS. Next time just send money.'
Do show you've made an effort with good quality paper and legible writing.
Do send a text or phone on the day if a present is really thoughtful or generous, but always follow up with a hand-written letter.
Do check what your children have written to avoid excruciating explanations.
Do make sure you're thanking the right person for the right present, and putting it in the right envelope.
Don't write on lined paper ripped from a notebook.
Don't leave letters languishing at the bottom of your handbag waiting for a stamp.