Master A has been rather emotional of late, crying at the slightest scolding, feeling sorry for himself and developing an attitude. He’s turned from a chilled, happy-go-lucky child to an erratic one. It’s all rather unsettling.

I discussed this personality change with a friend who has three boys (yes, she looks a wreck most of the time). According to her, it’s down to his hormones. At around seven years of age boys get a surge of testosterone, causing all manner of weird mood swings.

Having three boys aged from 10 to 16, she’s seen and experienced it all in early years’ parenting. Her advice to me was simple – make sure he gets plenty of exercise.

It sounded like the type of thing you would say to someone taking home their first puppy but, of course, it made perfect sense. I know myself when I partake in any sporting activity it lifts my mood, makes me mentally stronger.

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I did some further research and came across the Youth Sport Trust’s latest report which found that young people who described themselves as “always happy” were twice as likely to take part in two or more hours of physical activity per day, and three times as likely to be a member of a school sports club.

Master A does PE just twice a week, and plays football on Saturday mornings. I realise now it’s not enough.

At the weekend, I mentioned to Master A that perhaps, as he was getting older, he needed to take up some more sporting activities, get some more fresh air during the week. I pitched the idea of going for a bike ride along the Thames Path.

He scowled: “It’s the weekend. It’s the only time I get to relax.”

He then ran out of the room, making a point (a very loud one) of slamming the door behind him. My patience thin, I marched out after him. He was in the garden, sprawled out on a sun-lounger, playing on the iPad. I glared at him.

He said: “What? You told me to get some fresh air and exercise. I’m in the garden – and I’m exercising my fingers.”

Working Mum, just wondering how I’m going to cope when Master A becomes a teen.