This is the feeling I search for in yoga classes. Being so content where I am that I can fully be in the moment. When I’ve checked my troubles and worries at the door and for an hour, I am fully present. I am only able to be fully present right now because there is no service or Wi-Fi and no option for me to exit the boat. But I sink into it, and it feels strangely blissful.

I create a reminder in my phone for three months from now, when I know I’ll be slogging through a dreary Ohio March, that reads: ‘Do a yoga retreat.’ Then I create another reminder, this one for January, that reads: ‘Start doing more yoga to prep for yoga retreat.’

‘Millie?’

I look around in confusion, wondering where my sister is.

‘Millie?’ Vanessa asks again. She’s staring straight at me. I’m about to shake my head, I can feel my spine stiffening and my neck muscles preparing to communicate Nope, you’ve got the wrong girl. But thankfully, my tongue regains movement and I parrot, ‘Yep!’ and try to ignore how much it must have looked like I was having a neck spasm. I spot Hugh giving me a weird look. I ignore it. If he’s not going to address that we might know each other, then neither am I.

Vanessa has already disappeared down the stairs and into the cabin. I follow her because no one else has got up and it appears I have been summoned.

‘Watch your head!’ she calls. Just in time, because I’m centimetres away from banging my forehead on the metal door frame. I grab onto the door with my hand and lower myself down into the first level of the ship’s cabin.

I take about six stairs down and land in a small area with three beds. Bunk beds stack on one side and the opposite wall holds a mattress piled with notebooks and papers and maps. There’s duffels and backpacks littering the space, along with various hats and sunglasses. There are dark-tinted windows that look out onto the deck. It feels homey and must be where the crew sleeps.

I follow Vanessa down another ladder further below deck. It empties out into a room with a table and a booth around it, backing up to a galley kitchen. The table is littered with suitcases and backpacks.

‘Grab yours?’ she says, making her way down a narrow hallway.

I lug my suitcase behind her, following her into an impossibly narrow room with four bunk beds. It smells slightly mildewy but seems to be clean, with worn wood bedframes and a patch of peeling paint in the corner.

‘Is this OK?’ she asks.