Sex education is a hot term at the moment. No doubt Mia will have heard it thrown around on television or radio, or she has seen one of the recent leaflets,Let's Grow with Nisha and Joe, aimed at younger primary school children. Some parents are concerned that an educational pamphlet spelling out a few body parts will corrupt their young children's minds. Others feel that it doesn't go far enough, citing research that shows the more our children know about sex, the less promiscuous they grow up to be.

Where you lie on the spectrum will, inevitably, influence your answer.

You may feel uncomfortable talking about it or feel that you should be ready with the facts immediately, fearing that otherwise the window of opportunity will close. “I would say you do know a lot more than you think,” says Petra Boynton, a psychologist specialising in sex education. “If your child came home with a maths problem and you said you didn't know how to do it, you wouldn't view yourself as a failure. So approach this in the same way. You can say, I'm not sure what this is about - let's find out together'.”

Your first response could be to ask Mia what she thinks sex education means. “Sometimes they have an idea and you can proceed from there,” says Christine Webber, a sex and relationships expert. “They may have got it slightly wrong but it will give them the chance to build on what they know.” You could clarify with a simple explanation such as: “It's all to do with grown-up people loving each other and how they can have babies if they want to.”

“Keep it anatomical and baby-focused, rather than getting into the area of how it's a pleasurable activity, which at 6 or 7 you don't really have to go into so much,” says Webber. Boynton agrees: “If you start by saying, 'It's all about where babies come from', you'll end up having to have that conversation. A reasonable way in is to say, 'It's about living with someone, having boyfriends and girlfriends and being in love.' Which is, for many of us, an easier place to start than an anatomical lecture on Fallopian tubes.

Just make sure that you're not like one mother who answered her child: “Sex education? That's something you learn at home, not at school, and that's the last I'll say on the subject.”

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