Katie and the perfect babysitter. Nowadays, Katie and her best friend Isis travel from school on their own.

They usually catch the 152 bus together. This particular evening, a girl from their class called

Samantha, was waiting at the bus stop. It was unusual to see her there, as she lived in another direction.

Isis asked politely,

Have you moved house?

And Katie thought,

I hope she hasn't,

because I could do without her snooty looks and snarky remarks on the way home.

But Samantha replied, no, I'm going babysitting this evening.

Is that fun? asked Isis. Oh yes, said Samantha. It's easy money. I'll give the kids ice cream for dinner and let them play with their iPads

on condition that they don't bother me or even make a sound. At eight o'clock my boyfriend comes

around and we sit on the sofa and watch Millionaire. The kids go to bed at half past ten just

before their mum and dad get back. Then I catch a taxi home with 50 pounds for my

troubles. Sick, hey? Isis smiled, showing her pearly white teeth, but her true feelings were

betrayed by just a tiny flash of green in her clear blue eyes.

Katie, who knew her almost better than anyone, knew this sign.

Isis was envious.

A few days later, ISIS had something to show Katie.

It was a card, the best quality sort, with a feel of parchment,

and on it, printed in beautiful script letters, was an advertisement,

Perfect Babysitting Service, Our Five Pledges,

Cooked Dinner, No iPads, Homework Done, Bed by 8.30. Good night story.

...