Their approach to food was also at odds. Amber had been through every food fad, feasting on bone broth, fasting, following the scripture of Paleo or Atkins or only nibbling organic, non-irradiated, biodynamic, fair-trade tofu, and was currently incredibly keen on quinoa. Emerald preferred food that was cooked in fat, drenched in salt and coated in chocolate, preferably simultaneously.

As if on cue, a huge plate of pasta arrived to interrupt my ruminations. Emerald grabbed her fork and started shovelling carbonara into her mouth with gusto. Still hungover, I’d ordered only soup, as everything else was too noisy. Kale-nosher Amber picked at her super salad while eyeing Emerald’s meal as though it were some long-lost childhood sweetheart.

As she forked in another huge mouthful, curvaceous, big-boned Emerald looked at Amber’s lithe limbs and dexterous movements. I could see that she was assailed by a consciousness of her own heavy clumsiness, which is why she snapped, ‘Eat a goddamn carb, why don’t you, Amber? It won’t hurt you.’

Amber shook her expensively highlighted blonde hair and swallowed the lettuce frond she’d been chewing. ‘It most definitely could. Have you girls had your cholesterol levels checked?’

‘Cholesterol?’ Emerald repeated. ‘Jesus, who cares? Yes, Ruby, why don’t you just get your cancer doctor to check your cholesterol. You must be very frickin’ worried about that.’

Amber started to retaliate but I raised my hand, in traffic cop mode, before placing the three cruise tickets on the table. ‘This is the remedy I want.’

My sisters greeted the tickets with the same enthusiasm you might welcome a syphilitic ulcer on your wedding night.

Amber was the first to speak. ‘Ruby, darling, I so appreciate the gesture, but I can’t leave the kids at such short notice. Bella has an exam. And Justin’s soccer final is on Saturday.’

‘You’ll only be away for three weeks,’ I persisted. ‘What’s the worst that could happen? Bella gets a bellybutton piercing and Justin a tattoo that says Love the Universe in Sanskrit?’

Amber shuddered theatrically, a strand of hair falling into her pretty face. ‘That’s what the tattooist says. In reality it probably reads khichdi and curry chicken.’

‘You forget, Ruby, that everything rates high on Amber’s parental anxiety meter,’ Emerald added disapprovingly.

I contemplated our middle sister. ‘Emerald’s right, you know, Amber. Stop letting your kids walk all over you. I love you so much, but you might as well get your own tattoo, right on your forehead, reading Doormat.’