"My six-year-old received a Christmas card so nasty, it left him in tears."

You just never know when Mama Bear will swing into action. She’s always there, hovering silently in the background. Waiting. Ready to pounce and defend when the situation calls; a spirit animal with a ferocious loyalty to her cubs. She’ll tear shreds off anyone who dares to interfere with her young.

Well, Mama Bear emerged from her cave today — with a vengeance.

It was the last day of kindergarten for my six-year-old; a day that was meant to be full of celebration and joy, and a time to reflect on those stand out shining moments of the year.

Instead, I was drawn to my son’s bedroom by the sound of crying — deep guttural sobs and moments of silence, as he struggled to compose himself. His shoulders heaving. His face broken. Eyes squinting and pleading. Tears streaming. The whole works. He was sitting cross-legged in the middle of his room, surrounded by candy canes and cards from his friends. Innocuous enough.

"Does this say 'hate', Mummy?", he asked, holding out a card and silently willing me to reassure him.

He hadn't misread it. For a moment, I considered telling him he had. But the message was clear and he understood it. The card read: "Dear [name], I hat you". Underneath was a perfect heart, upside down with a cross through the middle.

My own heart broke into a thousand pieces in an instant. Fleeting memories of rejection from my own youth came flooding back, tenfold. Moments long mothballed.

I told him I wasn't sure what the message meant. It made no sense, I said. He read it again, out loud this time. Pointing to each word. He told me whoever wrote it must have meant hate. He explained to me that the accompanying drawing meant hate too.

Needless to say it was a long afternoon. Many discussions were had about friendship, deception and yes… hate. Worthy dialogue, of course, under any other circumstance.

After much deliberation and back channelling, I took to Facebook — not to name and shame, but rather to call it out. I'd alerted the school and exhausted all available avenues but was still no clearer as to the origin of the card.

Within hours, I was contacted by a school dad who told me his daughter was behind the offending message. He said he did not think to read each of her cards. To his credit, he apologised profusely and assured me he had spoken to his daughter. He also said he'd be happy to privately discuss the 'reasoning' behind her card.

There are always extenuating circumstances, I get that. No child is perfect. I also understand that we're talking here about little kids. Kindy kids.

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But at the end of the day, one thing is unequivocally clear: hate is not a natural feeling for a six-year-old. Children learn to hate.

This story does have a bittersweet ending of sorts. When word got out about the card, several mums banded together - sending through video messages and photos of their children holding up hand-written notes and drawings for my little boy. "You are a good friend", "You are very nice", "Merry Christmas".

So let this be a lesson to all this festive season. Teach your children to love and accept. Be kind always. And please check your children's Christmas cards.