It could have been dreadful, our week of sickness. Two children and one father all grey faced, dragging themselves around the flat like damp flannels, spurning each tiny morsel of food, however delicious. We had been copiously warned about this inevitable combination of winter and nursery schools and had suitably dreaded it. But the odd thing is that when it happened I didn’t mind it too much at all.

I realise my tale would take on a different note had the illness been more serious, or had I caught the same lurgy. Touch wood, touch wood. Lucky too, the children were consequentially ill rather than simultaneously: we had one sorry child for the first two days and then another sorry child for the two days following. Father fell ill right in the middle.

But there was something intensely intimate about those days alone with each poorly child. We cuddled, read book after book, napped all curled up on the big bed. Food rules relaxed as I indulgently picked out all sorts of treats which might tempt them into breaking their fast. Each morning I carefully sifted through their clothes choosing the softest, stretchiest garments which couldn’t press them uncomfortably anywhere.

My sphere, intellectual and social, narrowed into these small yet immensely important domestic decisions, any self-absorbed once pressing concerns – going to the hairdressers, making job-related meetings, calling my friends – were pushed to, and left undisturbed at, the back of my mind. As a consequence, I felt pleasingly calm and focused. I don’t suppose this is a twin specific experience; parents with multiple children of different ages, with a sudden opportunity to focus on only one child, may say the same thing.

Sleep deprivation is hardly a joy, but it is never as bad as those relentless first few months with twin babies. Wide awake at 3am you worry about how terrible you will feel the next day. But the sun comes up and your body clock does remarkable things, leaving you feeling surprisingly sprightly until at least 8pm. The fear of grogginess is far worse than the feeling itself.

Then there was the reaction of the healthier, happier child. By contrast to their rather wan sibling, each in turn became resiliently independent; barely asking to be carried, sitting patiently whilst sick was cleaned up from the floor, trying hard to gently cheer up their usually more rumbustious playmate. It appeared to us that they understood the other child’s need was in this moment greater, and they would sacrifice their own desires to help. Peculiar, rather unexpected and a tremendous relief.

I say all of this, but now temperatures, nausea and lethargy have passed, there is the even greater satisfaction of seeing children and father vigorously tucking into big bowls of porridge and still asking for a banana to complete the meal. And how I shall enjoy us all charging around the park this afternoon, bracing fresh air, stretched legs and chubby rosy cheeks.

Why most of us find little children just about as sweet as candy floss from Brighton pier is at once obvious and obscure. The reasons, some individual and others surely biological, are many and varied. But one of them, it seems to me, must be the simple truthfulness of children’s expression.

For creatures without words, it is remarkable how honest little children are in their opinions, and how effectively they communicate the strength of their desires. I will give you an example. This morning I tried to change my son’s t-shirt, because the one he was already wearing looked a bit too small. He was outraged at the prospect of pulling on a new stripy green t-shirt instead of the old red one. He lashed his arms wildly, screeched with all his might and he pulled and pulled at the neck until I, worried he might hurt himself, thought this battle was not worth it and put the red one back on for him again. Satisfaction beamed from his face.

A less conflict riven example. My daughter is obsessed with bananas. She has been for months. It was one of her first words, and if the bananas are in sight at any mealtime, no matter what other delicacies may happen to be gracing her highchair tray – cheese or raisins or even yoghurt – she will imploringly stretch out her arms in the direction of the said fruit and chant the word until I concede. Her absolute ecstasy at being given a banana is so transparent. She squeals with delight, smiles at anyone looking and proffers it proudly before her whilst peeling it carefully. The joy is very charming, but a banana every mealtime is just not on – I have taken to hiding the bananas alongside the plates in the cupboard.

To come back to my point – there is no manipulation here, or shyness about expressing happiness. These children laugh without restraint, scream with rage when dissatisfied and peer with full, unabashed curiosity into every single cranny that interests them. Adults and older children, bound by social convention, do not behave like this. We spend hours, months even, discussing a slight regret with nuanced language tempered by a fear of offending, when a simple honestly turned down lower lip may have done the job just as effectively in a few seconds.

Perhaps it is because we become creatures with words – this acquired linguistic ability – that what we express is sometimes so far away from what we really feel. Who knows. But somewhere along the well-trodden road from babyhood to adulthood we lose this innate capacity for truthfulness and learn how to lie. I suppose by watching my children’s development I will see when they start telling fibs, and thereby discover that there is not a universal age for this passage from truth-telling to obfuscation.