Shopping for my honorary-niece Emily's third birthday was a truly eye-opening – and sometimes eye-watering – experience.

I remember the first time I saw Emily. She was barely a week old, teeny-tiny and, as the daughter of my best school mate and his wife, virtually family. When asked if I'd like to hold her, I was scared to in case I dropped her. She looked so delicate, so vulnerable, as if she were made of glass and a gust of wind could knock her off her changing mat and shatter her into a million pieces.

As Emily made the tiniest fist around my little finger, I suddenly understood why parents would jump in front of a bullet hurtling towards their children.

Later that day, while walking through the bustling city centre, I started to see the world through different eyes. Relentless speeding traffic belching out fumes, drivers shouting and gesturing angrily at each other, drunks fighting and swearing in the street, putrid litter – it all seemed too loud, too aggressive, too dirty and too dangerous for Emily's brand new eyes and ears. I started to see hazards at every turn.

Three years later, while shopping for Emily's third birthday present this week, I was aghast at some of the choices presented to me.

I could have bought her a tiny T-shirt bearing the slogan "I know what boys like", "wanna play kiss chase?", "PIMP" (which apparently stands for "poop in my pants"), "porn star in the making", "the condom broke" and many others not suitable for a family newspaper.

I could have bought her a plastic doll wearing more make-up than a drag queen and dressed like a hooker. I could have bought her heeled shoes made to fit three-year-old feet. I could have bought her scribble-pads, colouring-in pens, bedding and more stamped with the Playboy bunny logo. And for her seventh birthday, I could even buy her a padded bra. Creepy.

When a friend of mine told her young daughter she needed some new long socks for school, her daughter asked if she could have some "with braces on". When her mum didn't know what she meant, her daughter showed her a pre-teen magazine article about a music video by popular girl band The Saturdays featuring the young female band members wearing black stockings and suspenders. Shudder ...

I cringe when I see how some parents let their little daughters dress. While shopping in a Bristol supermarket yesterday, I saw a mum whose tiny daughter was wearing an official Pussycat Dolls "doll in training" T-shirt. Now, for anyone who doesn't know, the Pussycat Dolls are a pop group that grew out of a burlesque dance troupe and they wear very little (think push-up bras, leather hotpants and thigh-high heeled boots).

Wrong-ola. Mind you, what can you expect from a mum wearing a tight, cleavagey top emblazoned with "bitch" in cheap diamanté?

This sick sexualisation of little girls has to stop. It's dangerous. Little girls should stay "little" for as long as possible. No daughter of mine will ever wear a midriff-bearing crop-top or a T-shirt that says "so many boys, so little time".

And while we're at it, if I had a teenage daughter, I couldn't in a million years stomach buying her a pair of tight trousers with the label "Miss Sexy", the infamous garment recently banned by Nailsea School.

What are the parents who buy their daughters these inappropriate things thinking? And what message does it send out to their kids?

I don't care if your daughter begs, pleads, emotionally blackmails you or throws a screaming hissy fit in the middle of the shop and I don't care if all their friends' parents have already caved – you're the parent. Say "no".

What's more important - being a "cool", popular parent or doing the right thing?

If you don't look after your kids properly, you don't deserve to have any.