I want to go to the Adventure Dome more than anything.

The leaflet says there’s an intergalactic space ride where you go on this giant rocket that’s so real you think you’re going to another planet, and a jungle room where there are snakes and giant lizards you can hold. I bet Elin won’t be interested in any of that. She’ll just want to play in the stupid fairy castle with the other girls in our class.

What’s the point of going to the Adventure Dome if you don’t do all the best things?

I bet Paige would like the space ride and the jungle room. We spent all lunchtime yesterday hunting for ladybirds in the grass by the football pitch. We didn’t catch any since it’s nearly winter, but Paige found the broken shell of a magpie’s egg, and I found a spider with legs the length of my little finger. She knows almost as much about insects as I do, and she likes the same nature programmes on the BBC. She doesn’t watch the Discovery Channel though. Her mum can’t afford to pay for satellite TV.

I wish Paige was my stepsister instead of Elin. I bet she would have been dead excited to get my Transformers torch, instead of making a face like she was sucking lemons when she unwrapped it.

I drum my fingers against the wall and count to twenty as I listen to the minibus reversing out of the drive, waiting till it turns onto the main road. Dad and Liz said I have to stay out of the kitchen until the girls have gone, but I think that was more Liz’s idea than Dad’s. He wasn’t happy that Elin wouldn’t let me go with them, but I don’t think he can take any more arguing with Liz.

It’s like we’re all walking on magpie’s eggshells round each other now, trying not to break anything. It was like this at home before Dad left, and I’m scared if I do anything to upset him and Liz then Dad will leave again, and what’ll happen to me after that? Mum doesn’t want me in California, and Liz and Elin definitely don’t want me here. Where would I go?

Maybe I could move in with Paige and her mum. I think Paige would like that. She doesn’t have any brothers or sisters or a dad, and she seems pretty lonely.

I hope she has fun today. I hope Rachel and Lauren aren’t mean to her when I’m not there to stick up for her. And I hope Elin isn’t going to make her feel bad for having a fake invitation instead of a real one. Especially as I didn’t tell Paige it was me who wrote it.

“Jamie? Are you going to give me a hand in here?”

Dad’s in the kitchen getting the party food ready, and he’s letting me know the coast is clear and I can come out. I run down the hall and charge into the kitchen at top speed, tripping over a chair and knocking over some of the cups Dad is laying out on the table.

“Careful! Elin will have a fit if you wreck her cake,” Dad warns, checking to make sure I haven’t dented the pink icing. It’s the biggest cake I’ve ever seen, a triple-decker sponge cake in the shape of a giant fairy castle with turrets. It’s got so many sweets on it I’m pretty sure one bite would rot all your teeth. After Elin refusing to let me go to the Adventure Dome, I grin at the thought of her spending tomorrow at the dentist getting her teeth pulled out one by one. Then I remember that Paige will be eating the cake too when they come back, and suddenly it doesn’t seem as funny any more.

“No, not sandwiches Jamie, we talked about that.” Dad closes the fridge door before I can start pulling out the jam jars and cans of cream I’ve stashed there.

“But my Mad Jamie Specials are the best thing ever!” I protest. “Everyone will love them.”

“We’ve already got enough food to feed an army,” Dad says, pointing at the piles of buns and bowls of trifle and sweets. He’s got a point, but I don’t want to admit it.

“Not even a few? I can just do one each.”

“Not today Sandwich Man, you know Elin doesn’t like them.”

“She’s never even tried them,” I mutter, picking up the extra one wrapped in cling film I’d left on the kitchen counter for her. It was a special birthday one, and she’d just pushed it away and said, “Yuck!” when I’d offered it to her this morning.

“And put that one away in the fridge. You can blow up these balloons instead.” Dad hands me the pump. “I need to finish setting the table.”

The cardboard tube’s a bit rubbish, and no matter how hard I pump there’s only a tiny little puff of air coming out the end. I’d much rather use lemon juice and baking soda to blow up the balloons, but I don’t think Dad would let me do one of my science experiments just now. He’s looking a bit stressed. I think he’s worried about what’s going to happen when all the girls come back and I join them for the party food. He doesn’t need to worry. I’m going to be on my very best behaviour.

I’m only one meltdown short of being kicked out of this family for good.

I can’t afford to do anything wrong ever again.