We exposed our winter-white limbs to the kindly autumn sun and ate prawns and snapper and blue-eye cod and drank Petaluma wine in a sort of Proustian ecstasy.

Back in Sydney, everything was verdant: tender new shoots on the fig trees, camellia hedges studded with pink buds like jewels. Staying in Leichhardt with friends, I walked to the deli in the mornings to buy fresh ricotta, still warm, and tiny almond biscuits from the Italian bakery.

It felt baptismal: lying on our backs in the warm water, looking up at blue sky and tall eucalyptus.

I met an old friend in Bondi, walked the coastal path and sat on rocks in the violet evening light watching the surfers at Tamarama. He and I did as we always do wherever we are in the world, "Tired the sun with talking, and sent him down the sky."

Elizabeth had designed the wedding invitation with a motif of intertwined oak and gum and my job was to echo this entente cordiale with the decoration of the cake. I raided a friend's garden in the mountains for oak leaves not yet fallen and crept out into the Leichhardt streets at dusk to pick flowering gumnuts.

The venue was at Sackville, north of Sydney on the Hawkesbury River; close family on both sides rented cottages and we spent the days before the wedding getting to know each other, walking, kayaking, swimming and cooking meals together.

The ceremony was held on a promontory above the river and began with a Welcome to Country from Chris, a gently spoken Darug man. I watched my four-month-old granddaughter, peaceful in her mother's arms, and made a mental note to tell her all about it when she is older.

Chris lit a small fire of gum leaves and we walked through curling smoke to cleanse any dubious spirits, arranged ourselves on benches and listened to Alex and Elizabeth make their vows, soft blue and gold light all around, and to unaccompanied voices singing Purcell.

Afterwards I found myself beside Lisa, mother of Alex's half siblings, the two of us tottering in high heels down a stony path towards the reception. We nodded in complicit acknowledgement of silly shoes. "I hope you felt okay about that," she said, meaning – I guessed – her presence. Or perhaps the celebrant calling her Alex's stepmother, which I'd thought odd: it's not as if I was dead. But as he has had supper at their house practically every Sunday night for five years, I told her she had more than earned her spot on the front bench. I linked my arm in hers. "Anyway, we are family."

People drifted about drinking pink cocktails, looking gorgeous in a hipsterish way. There were only two loos and finding the ladies' occupied I used the men's next door, coming out to find a young man in a kaftan waiting patiently. "Oops, sorry," I said. He shrugged: "We're all fluid here, babe. Look, I'm wearing my dressing gown."

This was a homegrown affair: music, beer, decor and food all provisioned by friends, including the amazing Marty Boetz in his Cooks Co-op tin shed. Star of the show was Elizabeth's dad, Andrew. A true hustler, he ambled to the microphone, shuffled some bits of paper and began, "Well, it says here on www.fatherofthebridespeech.com …" Then proceeded to make the sweetest, funniest, most moving and brilliantly timed wedding speech, which bode well for the alliance of the two tribes.

And just now, back home in the UK, there is a ping on my phone; I open up an audio message and hear the sound of a foetal heartbeat. Due in December: a poster baby for our very own Pommy/Aussie family.

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