Now call me old-fashioned, but I thought this reaction was a little extreme.
I'd just told a mum in the playground how my son Lucas (who was proudly parading a purple fibreglass plaster-cast at the time) had broken his arm by tumbling head first out of a tree.
"You let him climb a tree?" she went on. "You were THERE when it happened?"
Err...yes. I was.
And I didn't provide a safety net or harness either.
Now if I'd told her I'd allowed my seven-year-old to paraglide solo off Big Ben or walk a tight-rope blindfold across the Thames, then I could have understood her incredulity.
But trees – and boys – and climbing – well, they go together, don't they?
Apparently not, these days, if statistics are anything to go by.
A study by Play England found that we're wrapping up our kids in a cotton-wool culture of safe, soft play.
Over half of all children have been prevented by their parents from climbing trees, for example, whilst 21 stopped from playing tag and chase.
Yet, these outdoor activities - deemed too dangerous for today's generation to take part in - were those most fondly remembered childhood games by 70 of children questioned wished they had more freedom to enjoy these kinds of pastimes.
But it's not just adventure we're depriving our kids of. A study published last month in a child health journal also found that today's 10-year-olds have less muscular strength than children born 10 years before them because they don't do activities like climbing trees and ropes any more. It's action games like this that boost muscular strength so that they can hold their own body weight.
I've always thought it important to give my two sons as much strenuous outdoor play as possible and to allow them to take measured, calculated risks, too.
Don't get me wrong, it's not come easy - my partner has often had to tell me to loosen up, step back and let them get on with it as they teetered along logs straddling streams, rattled across precarious home-made ramps on their bikes, or swung perilously from tatty swing ropes in the woods.
Oh yes, my heart has been in my mouth more times than I like to remember.
Of course there have been numerous occasions when my mother's protective instinct has had me almost reaching for that blanket of cotton wool.
But I stop myself most of the time, remembering an article I read some time ago, which concluded that children who don't take risks can grow into wary, unadventurous adults who underachieve.
The message was that you've got to let your child experience a degree of danger or hazard or they won't learn self-reliance or that satisfying sense of achievement when they succeed at something on their own. Children who take risks and get bumped and bruised along the way tended to be more resilient and resourceful as adults too.
So when Lucas began to show a keen interest in climbing trees, I forced myself to allow him to branch out, as it were. Cue nervously shaking knees (my own) and heart-in-the-mouth again.
Naturally, I warned him of the risks and necessary caution he needed to take. How to check whether a branch was safe and could take his weight, the importance of taking his time and so on.
To his credit, he's always been a sensible, safe and adept climber.
So on this particular day last week when on a day out, he and his brother started to climb a tree together, I casually called out my usual 'be careful' and 'not too high' then subsequently relaxed on a sunny bench nearby and chatted with my partner.
The boys had been sitting in the tree for a good 10 minutes when I heard them suggest a race higher up. Before I could warn them that this was a very bad idea, Lucas had started the race and came tumbling head long out of the tree from a height.
Needless to say, it all happened in sickening slow motion.
Since then, I've asked myself this: was I too slow in coming forward? Had I not drummed it into his head enough that racing on anything from which it's possible to fall from a height (racing up and down the stairs at home has always been a no-no) is a risk really not worth taking? Was I right to let him climb quite so high in the first place? And should I have been standing under the tree watching his every move rather than chatting with my partner on a sunny bench nearby?
Moreover, had I been misguided in letting him take any sort of risk like this in the first place.
Of course I partly blame myself. That's what mothers do, no?
And if I've relived the moment he fell once I've relived it hundreds of times in the past week. I've also imagined how much worse it could have been and I am constantly thanking my lucky stars.
So, post plaster-cast, will climbing trees be out of bounds from now on and will I encourage more risk-free playtime?
Of course, I'd love to. But wouldn't I be selling my son short if I did?
He's clever. He's got his own mind. And he has learnt a valuable lesson. (That he will come a cropper unless he takes due care and attention. That it hurts to fall from a height. And so on.)
I like to think that he will now be the least likely of all children to fall from a tree.
Since the incident, I've done a bit of internet research and was surprised to find that three times as many children are admitted to hospital after falling out of bed than falling from trees. And that, whilst broken bones were a matter of course in hospital casualty rooms in days gone by, now doctors are just as likely to be treating obesity and, in the future, computer related RSI injuries in children.
So, no. Trees won't be out of bounds.
And my heart will continue to live in my mouth.
Do you agree it's important to let children take calculated risks?
Or are you very protective? Tell us what you think.
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