This is the sequel to Milk, my other one shot. To add a bit of explanation (that I did not give the last time) - the family are not poor. But Mr and Mrs Black have passed the line on "mad" and keep their two sons locked in the house. Sirius is nine-on-ten. Regulus is five.

Sometimes, at night, I get frightened. I'm frightened when the lights go out, and my whole room is black. I can't see anything, but I hear things. I hear Mother and Father whispering together in their room down the hall. Sirius rolls over on his bed, which is next to mine.

On some nights, Mother and Father don't whisper. Sirius lets me come into his bed on those nights, because the noises scare me. They make funny sounds, like dogs howling at the moon. All night I hear dogs howling and thumping against the wall; and then there's the squeak. Sirius says the squeak is their bed moving, and he shows me how his bed squeaks as well.

I don't think it sounds anything like Mother and Father's squeak.

Their squeak is loud, like angry mice. It goes on for ages some nights, and only for a few minutes the next. Squeak. Squeak. And then quiet again, and Mother is crying.

A bit later, Mother's belly is growing a bump.

'Sweet Merlin, this thing is kicking like the devil,' she says, rubbing the spot where it kicks her. Mother is different now, and I don't understand it.

She pours porridge for Sirius and me. Real porridge, with no maggots. The milk hasn't got lumps, and it's white. She pats my head when I straighten the pillows on the sofa, and she calls Sirius 'love'. She never called Sirius love before. On Monday, she gives me a biscuit for being a good boy. I've only had the mouldy biscuits Aunt Elzira brings us on Christmas; this one is chocolate, and Mother's baked it fresh, just for me and Sirius.

'Be a good lad, Reggie, and bring your mother a glass of milk.'

I can see Sirius's mouth tighten into a thin line, like it always does when he is frightened. Sirius hates milk.

'Have you thought of a name?' Father asks, and sets his newspaper down on Sirius's porridge. It's soggy and gray, but Sirius digs it out and puts it in Father's coffee.

Mother's lips go tight like Sirius's. It makes me want to hide, seeing her lips like that. That's the way she looks when I am about to be very sorry. I bring her the milk.

'Thaddeus,' says Mother.

I wonder who Thaddeus is and why he needs a new name. Hasn't he got any parents? I try to ask Sirius when Father sends us to our room, but he just holds his fingers to his lips. No asking questions. All day I wonder about Thaddeus and Mother's bump. What's inside there? Why does it kick? Maybe it doesn't like being inside Mother.

Sirius is drawing on the wall next to his bed. Mother gets angry when he does this, and makes him scrub it off with his knuckles, but he doesn't care. Sirius doesn't ever care. He draws on the wall with bits of chalk and blue crayon and pencils he nicks from Father. Now he is colouring a baby in a blanket. I watch him add a blue crayon blanket and blue eyes like Father's.

'Who's that, Sirius?'

Sirius isn't listening. He draws chalk hair and pencil lips. The baby is crying; he draws tears next. For a long time, Sirius doesn't answer me. He draws and draws until I get bored and play funeral with my maggot collection. They've all died off, and Mother hasn't given us any soup, so my collection is stinky from rotting in my sock drawer. Sirius's drawing a mother now, and then a father. They smile at the baby and hold it. The mother is singing. She has grey eyes, like my mum. My maggots are boring now, and I want to see what Sirius puts next.

Very carefully, he draws two tiny pencil people behind the father. One is taller than the other, and they hold hands, watching. Everyone is happy in the drawing, except for the two little people in the back. They frown at the baby and try to reach for the father, but he is ignoring them.

'Us,' Sirius tells me, pointing to the tiny people. I see Sirius's grey eyes and curly hair. Mine are blue, with blue lines running out of them. 'Mum, Dad, baby.' He points out every single one of them.

'Are we getting a baby, Sirius?'

Downstairs, a door slams. Father's gone off to work, and Mother will be in the kitchen. I hope her bump has stopped kicking.

'Course we are, stupid. Mum's pregnant, isn't she?'

Sirius makes a nasty face and scribbles out the baby's eyes. First in blue, then pencil, and then chalk. It looks like a marshmallow.

'Is the baby Thaddeus?'

Sirius looks at me for a long time. His eyes have gone squinty, and his hands are shaking. It's not cold. 'Just shut up, will you? You're just a stupid little twit, anyway. What do you know?' He throws the chalk at me; it hits my lip, but I don't move. I don't care if I've got chalk on my face, because Sirius is stomping out of our room, and I'm sure Mother will be angry with him.

'Wait! Sirius, don't leave me here!'

But he's gone. Down the stairs, out the door, into the garden. I've never seen the garden before. Father boarded up the windows a long time ago, and little boys are never allowed outside. Sirius sneaks out sometimes. He comes back with stories about lizards and squirrels and all sorts of things I've only ever seen in books.

Mother is singing down in the kitchen. She sounds like Aunt Elzira's cat does when Sirius and me try to tie her tail to the chair leg. Mother is going to have a baby. That's why she's got a bump that kicks when she eats porridge. I wish Sirius would come back. I've got more questions, like: Why does a baby live in my mother's belly? How will it get out? Maybe that is why it was kicking her. It wants to get out, but it doesn't know how.

I think I'm going to help it.