Zoe Spencer-Silver, 15

One of the bad things about being an only child is the reaction you get from other people. They think you're spoilt - you see that look in their eyes. And then you have to prove you're not spoilt, although you know you're not and nor are most only children.

When I was little my friends thought I was lucky being an only one, but now when I tell friends I can tell they're thinking, that must be hard ... She's not got a sister to go shopping with, or a brother to help with her homework. All my friends have brothers and sisters. It can be a bit lonely - like when your parents go out and you're on your own with no one to talk to. I spend a lot of time chatting to my friends on the phone, and going on MSN. And I like it when one of my grannies comes over when my parents are out, because then I've got someone to talk to. I suppose, in general, I think there are more negatives than positives, but on the other hand it's all I've known and I'm OK with it.

Sarah Lee, 29

I went to boarding school when I was seven, and the hardest thing I found was making friends. Because I was an only child, I just didn't know how to do it. The thing is that when you're an only child you spend a lot of your time with grown-ups, you're not in a very child-centric home and you're often the only child in a gathering of adults. You're more of an appendage to your parents' lives than central to it: they can go on living more or less the sort of life they've always lived, only now you tag along too.

I found being an only child interesting, in that it gave me a place at the grown-ups' table and gave me a view into their world that children in a big family might not get. And I know it has, at least partly, moulded me into the person I am: I never like the idea of being one of a group, for example. If I'm pulled into a group I'm much more likely to go off and do something on my own, or with just one other person - I'm not comfortable with being one of a gang.

My parents are divorced now and my mother lives in the US and my father in the UK. I do feel very responsible for them - I feel responsible for their happiness, in a funny kind of way. I'm the closest relative in the world to each of them, and I am very aware of that.

Lorraine Mason, 36

I was a happy child: I had the undivided love and attention of two people, and it made me very confident and secure. I know some only children feel stifled by their parents, but that wasn't my experience. I found it enriching, which I think is mainly because we get on so well.

Because my childhood was happy, my instinct was to replicate it in my own family, and have just one child myself. I might have done that, but then a few years ago a close friend, who like me was an only child, was killed in an accident. It was devastating for all of us, but of course especially for his parents. It's a double blow for parents when they lose an only child: firstly because they were so close, and secondly because there's no one to go on for.

I came away from the funeral knowing I could never survive what that couple were going through, and it made me decide to have more than one child. My eldest daughter is four and a half, and my second child is 12 weeks old. I suppose the big age gap reflects the fact that I wanted to give my elder daughter that "only child" experience for as long as possible.

I do find having two children scary. The problem is I've absolutely no experience of this kind of situation: nothing in my past has prepared me for having to divide myself between the needs of these two little people, and the guilt is hard when I feel I've not been there enough for one of them. And on a practical level, things like sibling rivalry are going to be a whole new ball game.