As the year-end school holidays roll to an end, I have to confess that I am secretly rather relieved.

Of course I'm glad to have devoted much of the past six weeks playing, bonding and just being with my two kids. But a big chunk of the time was also spent nagging, chiding and - more often than I care to admit - yelling at them.

What sets me off is usually the squabbling, which has intensified with no school to keep them apart. I'm talking about annoying, incessant quibbling that sometimes erupts into open warfare involving fists, legs and even teeth on one occasion.

Both have hit a few major milestones this year, which means they now have more ammunition at their disposal to do battle.

My son, who starts Primary 1 on Thursday, has been devouring story books with more words than pictures on his own. Inspired by his recent favourite, the Horrid Henry series by Francesca Simon about a boy who is every parent's worst nightmare, my son thrives on coming up with a string of rude names for his younger sister.

Ugly toad, dung beetle and lumpy pillow are just some of the monickers he spits out with glee that grows in direct proportion to her distress.

My daughter, who turns four in March, now boasts a wider vocabulary too. She can't quite read yet, but she sure can return volley in their daily spats.

"Don't touch my toys/books/crayons," her brother might say.

"They are not yours," she will reply.

"Yes, they are!"

"No!" she shouts back, then adds: "Mama says we must share."

"I am older than you. You must listen to me."

"You are just a little boy," she retorts, unimpressed.

If all else fails, she has learnt to employ tears as a strategic weapon.

"Mama," she will come wailing, the corners of her mouth weighed down as if with untold grief. "Gor gor said I am a stupido."

"Do you think you are one?" I ask. She shakes her head and the tears that have been welling in her eyes zip down her face.

I steel myself against reaching over to thumb them away - my husband and I have agreed not to encourage her drama queen antics lest she becomes adept at emotional manipulation.

Instead, I tell her, for the umpteenth time, to ignore her brother whenever he utters anything rude or unpleasant and leave us to deal with him.

"Mama says don't care about you," I hear her say as she heads back into the fray.

In retaliation, my son taunts her in a sing-song voice: "Mei mei is a crybaby. Mei mei is a crybaby." And the sniping, over everything and nothing, starts afresh.

For parents who are wringing their hands over how to keep peace at home, there are reams of research on the impact of sibling rivalry and how to deal with it.

The problem, though, is that these studies are sometimes contradictory. One published in the July issue of the journal Pediatrics found that kids who were bullied by siblings suffered, not surprisingly, greater levels of mental distress.

An important implication of the study, say researchers from the University of New Hampshire, is that parents and caregivers should take sibling aggression seriously.

Research released by the University of Missouri last year agreed that sibling rivalry can cause lasting emotional damage, but warned parents against stepping in. Instead, they are advised to set clear ground rules, such as knocking before entering a sibling's room, to bring peace and harmony.

Then there was a study by the University of Cambridge in 2011, which found that fighting between siblings boosts the social skills, vocabulary and emotional development especially of younger brothers and sisters.

"Parents who are being worn down by constant bickering among children should take comfort in the fact that their children are learning important social skills," says researcher Claire Hughes.

I, of course, choose to pay more heed to the last study, not least because it gives me hope that something good might come out of a vexing situation.

Recently, a friend recalled her horror of being a mother to three fractious boys years ago. An only child, she grew up playing mainly with other nice little girls, so it was a shock to see her kids come to blows. One day, she called her husband at work in tears: "Your sons are fighting, I don't know what to do."

Today, her boys, all young men with impeccable manners, enjoy a close relationship.

I, too, believe years of sparring with my younger sister when we were growing up have drawn us closer. It is hard not to forge a bond with someone with whom you fight tooth and nail one minute and then turn to for help and companionship the next.

We still laugh about those days when we would sometimes spend what felt like an eternity with our faces inches from the floor, all because neither of us would let go of the other's hair. Through our endless fights, we learnt to negotiate, compromise and, most importantly, to forgive.

So as drained as I am, I'd rather have my kids trade barbs than shut each other out. As long as the aggression is contained, I doubt the squabbles will leave permanent damage.

I'm assured that deep down, they have a soft spot for each other, for the fights usually end as quickly as they start.

Just the other day, I heard my son chant, "Mei mei is a b-i-g f-a-t p-i-g", knowing full well she can't quite spell yet and would thus get all het up, wondering what new rude name he had come up with.

As her insistent cries of "What did you say?" rang out, his strident tone suddenly softened.

"Mei mei, we won't be in the same school next year. Will you miss me?"

Her mood switching just as quickly, she replied: "Yes, but we can play together when I come home. Gor gor, you wait for me, okay?" I pray they will never stop loving each other, no matter how bad the fights get.

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