My friend Ellie is bewildered. Recently her son's 16-year-old girlfriend was leered at outside the station.
'So I said to her,' says Ellie, 'but look at what you're wearing. It's very revealing.'
At this point, son's girlfriend burst into tears.
Ellie was shocked. 'I said, "What's wrong? What have I said?" And she said, "You hate my clothes." And I said, "No I don't, pet. It's just there aren't enough of them."'
Of course girls should wear what they like. It's about expressing personality. It's about loving fashion. But mums look at tiny skirts and plunging necklines and heavy eyeliner and think, but is it safe? My baby's about to get on a bus, and some men won't realise this is joyful dressing-up. They'll think it's some kind of come-on, the perverts, and then she'll be in danger...
But this is a treacherous thought. It implies that girls are to blame for what men think. (Oh, that horrible rape argument - she was walking home at night in a figure-hugging dress so she was asking for it.) Why can't girls have the same freedom as boys? Even now in 2010, there are all sorts of unspoken rules about what girls should and shouldn't wear, while boys wander round exposing skin and underwear and no one bats an eyelid.
So what should you say when your teenage daughter wants to go out in something that looks like a small silk petticoat? Nothing?
Fashion is a feminist issue?
Please, please don't go out in that?
'When I was 16,' says a friend, 'I used to have a long black coat that covered me from neck to ankle. So I could wear what I liked underneath.'
It's either that or a burkha.