‘Jeez,’ she grumbles, shaking us off without a word of thanks.

‘Well,’ exclaims Kit. ‘That’s charming. Of all the ungrateful little toads.’

I am about to reply, when Tui calls out my name, her frantic hand flapping even harder than the ferry’s red, white and blue flag.

‘What’s the matter?’ I begin, hurrying over and then letting out a cry of delight. Because there, lounging below us on an outcrop of flat rocks, is a whole little tribe of brown seals.

‘They’re amazing!’ I say, beaming first at Tui then at Griff.

Lifting my camera, I zoom in until I can see the small, inquisitive faces in more detail, delighted by their black beady eyes and short grey whiskers. Despite the proximity of the boat, most of the seals appear to be fast asleep, and I point out as much to Tui.

‘Lazy bones,’ she says laughingly, but I can see that she is enchanted.

‘Actually,’ I tell her, ‘seals are nocturnal – do you know what “nocturnal” means?’

Tui shakes and then nods her head.

‘Well,’ I continue, happy to put my lifelong animal fascination to some good use for once, ‘it means that they are active at night time. That’s when they prefer to catch fish for their dinner, and it must be quite hard work, because they are so tired afterwards that they sleep nearly all day.’

‘Wow,’ she says, her eyes wide.

‘Brown seals like those have got fingernails, just like us,’ I tell her, wiggling my fingers and feeling hopelessly touched when she follows suit. ‘They use them to climb up on to the rocks.’

‘Will they bite me?’ Tui wants to know. She looks so serious as she says it that my heart almost breaks.

‘They can be a bit stroppy, Tu,’ says Kit, who has just appeared behind us, ‘but you’ll be OK as long as you don’t get too close.’

‘They’re extra aggy at the mo,’ Griff puts in. ‘It’s mating season.’

As the boat pulls away and heads out into open water, Tui rubs her stomach and announces that she’s hungry enough to eat three sandwiches, two chocolate bars and a seal, prompting a laughing Kit and me to venture down one deck in search of lunch.

‘So,’ he says, as we join the back of a very long queue leading up towards a kiosk, ‘Tui has not stopped going on about that riding lesson you gave her. Allie reckons you must be a pro?’

‘Tui is much better than she gives herself credit for,’ I reply honestly. ‘You said she first sat on a pony as a baby, right?’

‘I think it pretty much goes with the territory if you’re Bonnie’s daughter,’ he says, not noticing me wince. ‘But as you know, she’s nowhere near confident or able enough to go out alone yet. Her balance is a bit off – it’s part of her condition.’