"love to." i nod.

anna and i talk about having coffee every time we see each other-which would be getting on for two years now-and it hasn't yet happened. but somehow that doesn't matter. somehow that's not the point.

"that bloody travel project," anna is saying as we walk toward the school entrance. "i was up at five a.m. finishing that off. up your street, i suppose, travel!" she gives a cheerful laugh.

"what travel project?"

"you know, the art thing?" she gestures to her container. "we did a plane. utterly lame. we covered a toy with silver foil. hardly homemade, but i said to charlie, 'sweetie, mrs. hocking won't know there's a toy underneath.' "

"what travel project?" i say again.

"you know. make a vehicle or whatever. they're showing them all off at assembly.... charlie, come on! the bell's rung!"

what bloody travel project?

as i approach mrs. hocking, i can see another mother, jane langridge, standing in front of her, holding out a model of a cruise ship. it's made out of balsa wood and paper. it has three funnels and rows of little portholes cut out perfectly and teeny clay figures on top, sunbathing round the blue-painted swimming pool. i stare at it, speechless in awe.

"i'm so sorry, mrs. hocking," jane is saying. "some of the paint is still wet. we've had such fun making it, haven't we, joshua?"

"hello, mrs. phipps," calls out mrs. hocking cheerfully. "nice holiday?"

mrs. phipps. it sets my teeth on edge every time i'm addressed this way. i haven't got round to becoming "ms. graveney" for school purposes. truth is, i'm unsure what to do. i don't want to unsettle noah. i don't want to make a big deal of rejecting his surname. i like having the same name as noah. it feels homey and right.

i should have chosen a brand-new surname when he was born. just for us. divorce-proof.

"mummy, did you bring the hot-air balloon?" noah is peering up at me anxiously. "have we got the hot-air balloon?"

i stare at him blankly. i have no idea what he's talking about.

"noah told us he was making a hot-air balloon. super idea." mrs. hocking descends on us, beaming. she's a woman in her sixties who lives in tapered trousers. she's so cool and unhurried, i inevitably feel like a gabbling lunatic next to her. now her eyes rest on my empty hands. "do you have it?"

do i look like i have a hot-air balloon about my person?

"not on me," i hear myself saying. "not exactly on me."

"ah." her smile fades. "well, if there's any chance you could get it to us this morning, mrs. phipps, we're setting up the display for assembly."

"right! of course!" i flash her a confident smile. "i just need to- one tiny detail- let me just talk to noah a moment." i draw him away and bend down. "which hot-air balloon, darling?"

"my hot-air balloon for the travel project," says noah, as though it's obvious. "we have to bring them in today."

"right." it's nearly killing me, staying bright and breezy. "i didn't know you had a project. you never mentioned it."

"i forgot." he nods. "but remember we had a letter?"

"what happened to the letter?"

"daddy put it in his fruit bowl."

i feel a volcanic surge of fury. i knew it. i bloody knew it.

"right. i see." i grind my fingernails into my palms. "daddy didn't tell me there was a project. what a pity."

"and we talked about what to make, and daddy said, 'what about a hot-air balloon?' " noah's eyes start to gleam. "daddy said we would get a balloon and cover it with papier-m