My youngest child and my brother's youngest child are peas in a pod.

Only months apart from each other in age, they are both mischievous, charming, and athletic - and the babies of both families.

But one is a little Aussie who plays AFL and calls everyone "mate", while the other has grown up saying "kia ora" and performing the haka.

New Zealand has been at the forefront of most of our minds this past week.

The volcano tragedy on White Island has claimed the lives of many, including Australians, as well as inflicting horrific injuries on dozens of people and leaving many questions unanswered.

But above all, it has stirred our emotions with this loss of life happening right on the eve of Christmas.

It actually didn't occur to me that my nine-year-old would be worried about our family, who all live in New Zealand, and this would play out while he slept.

Crying in his sleep, he was pleading for his little cousin to run faster to escape the explosions.

The reality is that our family is nowhere near this volcano.

Once we looked at the map, my son could see how far away his cousins were. They were safe, but he knew others were not.

He wanted to know what he could do to help.

And looking at his freckled faced, I could see he needed an answer, even though I didn't really have one.

So we began a conversation about organ donation.

I explained that skin was now desperately needed to treat the burn victims.

It was being sent from Australia and even the US to cover the wounds of those injured.

Without it, they may never recover.

Once we die our body parts are simply of no use to us.

But our eyes could help someone else to see, and our hearts could keep someone else alive.

My son asked if he could donate his body to his cousin if he ever needed it.

With tears in my eyes, I asked him if he would also be happy to be an organ donor for a complete stranger.

From a silly nightmare came the most amazing conversation.

Should I ever - heaven forbid - find myself as a mother in a situation where a decision about organ donation needs to be made, I will now know exactly what to do.

The gift of being a registered organ donor is not one that sits under the Christmas tree wrapped in sparkling paper with a bow on top.

And yet surely this is the greatest gift one could give, or receive.