I am a big fan of teenagers. I know quite a few. One lives in my house, along with his younger brother, who regularly thinks he is one.

They do incredible and smart things. They can be infuriating and mystifying, but their chat is hilarious and even educational. My teenage son and his friends have taught me a lot (not least of all the behaviours and phrases parents should definitely NOT display in their company.)

The idea that actual grown-ups might feel so intimidated by a teenager that they resort to insulting them online is deeply depressing.

Impressive activist Greta Thunberg is on her way across the North Atlantic in a zero-carbon sail to highlight the climate emergency we face.

The hideous tweets which followed the coverage of the 16-year-old’s journey smack of little more than classic playground spitefulness. But let’s not give rent-a-quote radio presenters and businessmen who thrive on the controversy their misguided tweets create any more publicity than they have had already. Let us, instead, turn to the amazing achievements of teenagers, at home and abroad, without whom the world would definitely be a poorer place.

Anne Frank wrote her diary from the ages of 13 to 15 and it has since been translated into more than 60 languages; Joan of Arc led the French army to victory at 17; Mozart was an accomplished musician and composer when he was still a child; Mary Shelley wrote Frankenstein when she was 18.

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Malala Yousafzai was shot by the Taliban in Pakistan because she stood up for the rights of girls to have an education – she went on to become the youngest Nobel Prize winner, at just 17. The Glasgow Girls were a bunch of teenagers at Drumchapel High when they helped to stop Home Office dawn raids on asylum-seeking families.

Pesky lot, those teens and tweens, with their talent and opinions and activism and determination to stand up for causes they believe in.

They should be sitting around in their bedrooms, pale-faced and angst-ridden, uttering only monosyllabic responses and generally being annoyed at everything and everyone.

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And yet here they are, championing change, righting wrongs, speaking up and taking all kinds of vile abuse from witless grown-ups, who really should know better, as a result.

To suggest someone cannot talk sense, or make a difference, or change the world, just because they have not yet hit their twenties, is patronising rubbish. Teenagers rock, as my teenage son would suggest I definitely should not say.