I was chauffeuring Master A to one of his numerous summer clubs earlier in the week, taking a day off work to do so.

I pulled on a T-shirt and a pair of jeans, happy to be free from the constraints of office garb. Windows down, shades on, a bit of Bieber on the stereo, and Master A by my side and I was in my element.

“What’s that, Mummy?”

Eyes fixed firmly on the road, I replied: “What’s what, darling?”

“That?”

From the corner of my eye, I could see him pointing towards me.

“I can’t look I’m driving. What are you pointing at?”

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“That! It looks weird,” he said, once again pointing towards me. “Is it muscle?” And with a prod of his finger on my bare arms, it dawned on me to what he was referring.

Bingo Wings.

I caught my reflection in the passenger seat window, the loose flesh, hanging, like a sloth, from my upper arms. The sight was ghastly.

Worse still was the expression on Master A’s face – the puzzlement, the obvious surprise of touching not muscle as he had first imagined but folds of flab.

I’d been body-shamed by my son – and it felt awful. I was embarrassed. My son had seen that his “perfect” Mummy because, of course, in his eyes I am, perhaps isn’t that perfect after all.

I tried pulling the sleeves of my tee down but it was to no avail – the wings just kept flapping.

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Master A prodded the skin again. “If they get any bigger, you’ll be able to fly,” he pronounced. “You’ll be like a flying squirrel or a bat! That would be awesome.”

His favourite Bieber track, Love Yourself, then came on the stereo to which he started singing along James Cordon-stylee, forgetting all about my Bingo Wings.

Needless to say I haven’t forgotten. Yesterday, I bought a set of kettlebells, a resistance band and a copy of Tya Botha’s Bingo Wings Blaster.

The next time Master A sees my bare arms they’ll be fit not fat – and I’ll be flying without wings.