It's 2.30am. The front door slams shut with a crash. I lie awake listening to footsteps plodding all over the house and above my head. Eventually, I can't stand it any more.
'What's happening?' I hiss at my 18-year-old who is standing, swaying slightly, under the landing light.
'Ah, um, there's someone staying the night,' he says. 'I've given them a sleeping bag.'
'Do you have to make so much noise?' I say grumpily.
'Sorry,' he says.
I'm woken again at 8am by my husband who is off to West Sussex to pick up three car seats (yup, that's right, eBay). I decide, in a burst of masochism, to do the ironing. I hate ironing. I need coat hangers for the shirts, and I know there's some upstairs in the spare room. Is it fair, I wonder, to risk waking our unexpected guest? But I am mean from lack of sleep. Yes, I think, perfectly fair.
Upstairs the spare room is empty. It looks exactly as it did when I stripped off all the sheets for washing a week ago. There's no sign of the sleeping bag. Weird, I think. Then I notice the white mattress cover in a tangled heap. I lift it up. There is a large yellow-brown lake in the middle, liquid slurry trailing off into several brown splodges all the way to the edge. It smells of something indefinable. Beer? Sick? Curry? Diarrhoea? A combination of all four?
I say to my son, 'I want an apology.'
'Sorry,' he says.
'Not from you. From him.'
My son nods, looking wretched.
'It's the way he just left it,' I say. 'Does he think it's OK to leave whatever mess he likes for other people to clean up?'
'I'm not defending him,' says my son, desperately, 'but maybe he was just too scared to say anything. Maybe he hoped that if he ignored it, it would all go away.'
'Scared of angry mothers?' I say.
My son nods.
With good reason, I think as I put the disgusting mattress cover to soak in the bath. Right now, if he was standing in front of me, I'd strangle him.
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