<i>The John Lennon Letters</i> is an exhaustive compendium of 250 letters, postcards and notes written by the Beatle from when he was a young lad composing a thank-you note to his aunty for a tea towel, to a few moments before he was shot down at the age of 40.

The John Lennon Letters is an exhaustive compendium of 250 letters, postcards and notes written by the Beatle from when he was a young lad composing a thank-you note to his aunty for a tea towel, to a few moments before he was shot down at the age of 40.

''Milk (3 cartons) Oranges Grapenuts (not flakes) …''

''… I know that you will always do the right thing, & remember to keep your temper & your word & be loving - sweet - Mummy.''

Don't sound very interesting, do they? One is a shopping list and the other an extract from a kind but conventional letter from an old-fashioned mum. But they are part of letter collections destined to be international bestsellers - because of who wrote them.

The first is from The John Lennon Letters, an exhaustive compendium of 250 letters, postcards and notes written by the Beatle from when he was a young lad composing a thank-you note to his aunty for a tea towel, to a few moments before he was shot down at the age of 40. The second is from Counting One's Blessings, a life-time collection of letters written by Elizabeth, the Queen Mother.

I don't remember when I stopped looking forward to peering inside the letterbox. Letters used to be personal, often fascinating and fun. Now the interesting stuff has migrated online. Which means that we treasure good old-fashioned letters, whether heartfelt or dashed off with a touch of humour, more than ever. Somebody cared enough to put pen to paper. If that somebody was a celebrity we're even more impressed, and if enough of these letters can be brought together, there's a book.

In the old days, of course, they wrote letters all the time. Biographers are among the first, outside close friends and family, to gain access to a celebrity's letters, as William Shawcross did with the Queen Mother's correspondence, and they often follow up the biography with an edited letter collection. It took Lennon biographer Hunter Davies a much longer time to assemble the letters for his book, because so many were held by dealers and collectors.

In the past, the most famous letter collections were revered for the light they shed on their subjects' inner lives, or on the history, politics or culture of their times; and letter collections such as Evelyn Waugh's also gave us some stunningly waspish entertainment. But have we taken our reverence for celebrity letters too far?

Some reviewers of these two books clearly think so; while some praised the Lennon compendium as a treasure for devoted Beatles fans, others scoffed at ''the John Lennon Post-it notes''. Nothing is too trivial, complained Neil McCormick in Britain's The Daily Telegraph: ''The bottom of the barrel has been well and truly scraped clean.'' The letters, Jarvis Cocker said in The Guardian, show ''an ordinary person doing ordinary things … Why is that interesting? Because that person has now acquired demigod status.''

There's arguably more substance to the Queen Mother's letters, but again, the poor thing invites mockery, with inevitable comparisons to Downton Abbey. Her determined air of making the best of everything gets to Craig Brown in the Daily Mail: ''Her single-minded pursuit of jollity makes reading this vast selection of her letters a slightly sickly affair, like being force-fed Violet Creams.''

In defence of the Beatle and the royal, they probably didn't expect their every scribble to be immortalised. And while I expect I won't bother reading either of these books cover to cover, there is virtue in a collection that includes the day-to-day banalities as well as the showpieces.

Even that cutesy letter to ''My Darling Lilibet'' needs context. ''Mummy'' was writing just after bombs hit Buckingham Palace, and she wanted to tell her daughters a few things ''in case I get 'done in' by the Germans''. She wasn't being boring. She was being very brave.

■Janesullivan.sullivan9@gmail.com

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