As I walked back from Lily’s house clutching my cardigan round me protectively, I kept thinking about what she had said about me having a nice figure. On holiday we had mainly been sightseeing, but on a couple of warm, sunny days we had gone to the beach. I had worn a bikini until a boy who was slightly older had wolf-whistled at me. I don’t know why, but it made me feel really uncomfortable. After that I had made sure I kept my T-shirt on the whole time. I’d never thought much about what I looked like on the beach before. I mean, I’ve never been fat, and it wasn’t like my shape had changed that much in other ways yet, but the bikini sort of emphasised what little change there was, I suppose.

I’m certainly not as developed on top as Lily, who has already started her periods. When I mentioned to Mum that I wished I would hurry up and start mine, she laughed and told me that the day would come soon enough. Mum started when she was eleven – the same as Lily – so she doesn’t know what it’s like having to wait and worry about it. I’ll be thirteen in a few months, so it’s got to happen soon and the whole thing is stressing me out. What if it happens when I’m at school? Will everyone know? Will it be really embarrassing? Will it hurt? I’m one of the youngest in our year and Lily makes me feel like such a baby if I try and discuss it with her. Mum doesn’t help either. She says that since she’s totally forgotten where she was (or how she felt) when she started her very first period, then it couldn’t have been all that traumatic. And she just rolls her eyes at me impatiently when I point out that people sometimes completely suppress their memories of really traumatic childhood events.

My feet suddenly felt a bit chilly and I looked down at the silver and blue flip-flops I’d bought in Greece. Now that I was back home I didn’t want to stop wearing them, but I had to admit that mid-April at home was a lot cooler than in Greece.

Fleetingly I wished we were still on holiday. We’d had the best time ever with Leo there to keep Mum in a good mood and to make us all laugh. As we explored the ancient Greek temples and other historical sites, he kept joking that it made him feel like he was in an Indiana Jones adventure, except that there were no baddies.

Mum kept saying that it was wonderful to watch Sean and Leo getting on so well together. Mum always says that not having a dad is especially hard on Sean because it means he has no positive male role model (our grandfathers both died before we were born). I try not to let it bug me that she never appears so concerned that I don’t have a dad. Her take on daughters seems to be that if they have a mother then that’s good enough, with a dad being a kind of very nice luxury. I know Mum didn’t see much of her own father when she was growing up – not because he was dead like ours, but because he was always away at work. But she tells me this as if it therefore follows that it’s no big deal for me not to have a dad, which is actually pretty hurtful because really it’s a massive deal, especially when I see how protective and proud Lily’s dad is of her. And the way Mum doesn’t seem to get that is just … well, horrible. In fact it sometimes makes me feel like I don’t have much of a mum either – not one who bothers trying to understand me, at any rate.

When I got home, Mum was in the hall doing yoga. It wasn’t odd for her to be doing yoga, but it was odd for her to be doing it in the hall where anyone could trip over her.

‘Mum, do you think I’ve got a nice figure?’ I asked, even though I know I’m not meant to speak to her if she’s in the lotus position with her eyes closed.

Mum has a really nice figure. She’s tall and slim – but not too slim as she’s always quick to point out (she’s never approved of all those size zero models and she’s always telling me how important it is for a woman to have some curves). She has long, straight black hair, pale skin and very striking blue eyes. When I was little I used to think she looked just like Snow White.

‘You will have,’ she answered, opening her eyes to look at me, ‘when you fill out a bit.’

‘Fill out a bit?’

‘In the right places, I mean.’ She sighed and shifted position on the floor. Clearly she hadn’t been properly into her meditation. ‘Why? What has Lily been saying about your figure?’

‘Nothing … it doesn’t matter … Mum, since when did you try to meditate in the hall?’

‘It wasn’t planned, Sasha. I was about to phone your grandmother and I suddenly thought it might help if I tried to centre myself first. But I think where Granny is concerned, my anxious thoughts are meditation-resistant!’ She stood up, smiling at her own joke. ‘Now you know, Sasha, that girls go through puberty at different rates and just because Lily has already –’

‘Mum, stop it!’ I said, feeling embarrassed. ‘It’s not that. It’s –’

But then Sean walked into the hall and I shut up abruptly. There was no way I was continuing this discussion with him listening. Not that my brother has got anything to celebrate yet as far as adolescent development goes. OK, so he’s nice enough to look at, I suppose – like me, Sean has our father’s brown hair and brown eyes, and sometimes when you look at a photo of our dad it’s like imagining Sean when he’s grown up – but he’s pretty small for his age. We were born prematurely – apparently that happens sometimes with twins – and Sean was the smaller out of the two of us. Even now, people who don’t know us tend to assume he’s my younger brother, which drives him mad.

‘Haven’t you done it yet?’ Sean asked Mum, sounding impatient.

‘Do I look like I’ve done it?’ she snapped.

‘Come on, Mum – stop procrastinating,’ Sean said.

Mum glared at him. ‘I didn’t realise you even knew such a big word.’

Sean grinned. ‘Blame Leo. He’s on a mission to improve my vocabulary. But come on, Mum. If you’re going to tell Granny you’re engaged, you might as well get it over with. Stop panicking. It’ll be fine.’

I just looked at him. Fine? Was he crazy?

As you’ve probably worked out already, Sean and I are very different in some ways. I’ve always been the sensible one. I like to think things through and make the right decision. I hate getting into any kind of trouble and Mum’s always been able to rely on me when she needs someone to lean on. Sean, on the other hand, is a bit of a show-off. He likes to play the clown and he always has the ability to make people laugh, even when things are tough. Unlike me, Sean definitely isn’t a worrier.

For example, if someone says something bitchy to me in school, I’ll spend that whole evening stressing about it, whereas if that happens to Sean, he’ll say the other person is an idiot (or worse) and forget about the whole thing in five seconds flat.

There are times though, when I reckon it is just being realistic to be worried sick about something – like now, for example. I mean, if you’d met my granny you’d totally get the whole emergency meditation thing. You see, Granny always has an opinion and she invariably thinks it’s her duty to pass it on in its purest form.

Her reaction when Mum had first started dating Leo was typical. ‘Are you seriously telling me he’s only twenty-eight? You have to be out of your mind, Annabel! You need a boyfriend who can be a father figure to the children – not one who can double up as their playmate!’

Ouch!

Oh yes – I could well imagine the horribly tactless and offensive things Granny would say to Mum now.

‘The trouble with Granny is that she’s way too honest,’ I said with a sigh.

Mum nodded. ‘It wouldn’t be so bad if only she’d impart her opinions with just a modicum of sugar coating.’

I nodded again. But even though that is definitely true, I don’t want you to get the idea that Granny’s all bad. OK, so Mum and her have always argued a lot – mainly because Granny is so bossy and thinks she knows what’s best for everybody. But whenever Mum’s feeling very low, she’ll still phone her to ask for her advice – and then get upset when Granny dishes out far too much of it. The thing is, whenever Mum is really in trouble, it’s always Granny who comes to the rescue. She practically lived with us for the first year after we lost our dad and she also stayed with us a lot during the first few months after Mum split up with Michael. And I have to admit that it was very comforting back then to believe that Granny always knew what to do, because I don’t remember ever feeling that way about Mum after our dad died.

‘Mum, you can always let Granny find out later,’ I suggested now.

‘Yes, Mum,’ Sean added. ‘It’s not like she’s going to congratulate you in any case. All she’ll do is freak out and launch into her “toy boy” speech again …’

‘That’s enough advice from you, Sean,’ Mum responded sharply. ‘And you’d better drop the word “toy boy” from your vocabulary, young man. You know the effect it had on Leo the last time he heard you use it.’

Sean went all sulky then, like he always does when he gets reminded of that. The thing about my brother is that even though he acts like he doesn’t care about anything half the time, as soon as you get to really know him you find out that there are a few things – and people – that he cares about massively.

I first realised Leo was one of them six months ago when I saw a side of my brother that I hadn’t seen in quite a while.

It began one Friday evening when Mum arrived home from work. We’d just started to realise that Mum and Leo were getting serious, and he was spending more and more time at our house.

‘Hey, Mum, how does it feel to have a toy boy?’ Sean greeted her jokily the second she walked in through the front door.

Unfortunately she wasn’t alone. Leo was right behind her. His expression turned icy cold.

My brother immediately blushed so awfully that his entire face went pink and both of his ears turned bright red. ‘Sorry …’ he mumbled, looking like he might be about to throw up. And that was when I first realised how important Leo was to him.

For the rest of the evening, Leo stayed cool towards Sean. He went home really early, which Mum blamed on Sean, making my brother feel even worse. When Leo came back the following lunchtime, Sean made a more direct attempt to engage him.

‘I’m just doing my English homework, Leo,’ he said. ‘Please can I ask you a question about it?’

Normally Leo would have been delighted to see my brother taking his homework so seriously. And he’d have been more than happy to switch back into tutor mode for a bit.

But instead he gave Sean a reprimanding sort of look. ‘I think you should be trying harder to do your homework on your own, Sean,’ he stated crisply. ‘Perhaps if you tried keeping your bottom on your chair and your eyes on the page in front of you for longer than a few minutes at a time, you’d actually find you could do it by yourself.’

Sean was totally humiliated and he beat a hasty retreat to his bedroom. Even Mum looked a bit surprised by the put-down, though she didn’t say anything.

Much later that day, after Leo had relaxed and watched one of his favourite films on the sofa with Mum, he went upstairs to talk to my brother, and things were fine afterwards.

But by that time I had come to understand two things I hadn’t realised before. First, maybe Mum was right about Sean wanting a father figure. And second, Leo was clearly hugely embarrassed and uncomfortable about the age gap between Mum and him. And we were going to have to keep our mouths firmly zipped on that subject from now on if we wanted to keep him in our lives.