The word golliwog has a special meaning for me. Like my five brothers, I went to a prep school in Edinburgh. I was only six years old, probably younger than most at the time. I was excited about leaving home for a new school, where, I had heard, deserts were served after every meal.

On my way to school from Edinburgh airport, to calm my nerves, my father told me funny stories. I remember him chuckling as he told me how two of his fellow students at the University of London had once asked to see his tail. He became pensive after that and moved on to his expectations of me, reminding me to behave myself. I understood what the consequences would be if I dared to disobey him.

Looking back now, I realise that my parents may have played down my blackness to avoid deepening the trauma of going to a school where I would be the only black face. This may have been a good thing because I didn't see myself as different. Unfortunately, boarding school wasn't about how I saw myself but what others saw when they looked at me.

I settled into the business of making friends. I didn't see my schoolmates as white, I just saw playmates whose hair I played with just as much as they played with mine. All that changed the day a boy kicked me and called me black Sambo after a particularly impressive shot in rounders. I think he felt diminished as the acknowledged big-hitter of the class. I wasn't offended by the name Sambo but I was taken aback by the word black. Why? Because it was a horrible reminder of the differences between us. I cringe when I remember that the best riposte I could come up with was, “Get lost, you white Sambo!”

And so, the name-calling began. It was as if that boy had prised the scab off a ripe boil. From then on, everywhere I turned, it was “black Sambo”, “oh, the black nigger”, with a guttural delivery, “nig-nog” and of course “golliwog”. The golliwog, which until then seemed to me a harmless jolly symbol of Robertson's Jam, had become a mocking parody of my difference.

Inevitably, I began to resent my blackness. I felt weak because I didn't have the tools to fight back. I didn't have any dirt on whiteness.

I returned to Nigeria at the age of 11, looking forward to blending in for once, only to find that my accent meant that I might as well have been white. I fought to belong and worked hard to shed my British accent. I took a keen interest in the history of my people and began to understand the significance of momentous periods such as the slave trade and later colonialism.

It was not until my university years, when I studied African-American literature, that I fully grasped the deeper implications of these periods on race relations outside Africa. Toni Morrison's Song of Solomon, for example, showed me how important it was for African-Americans to preserve their blackness to feel complete.

I think it was then that I realised the deep significance of cultural identity and how rootless one is without it. I vowed that my children would grow up being proud of their heritage. Now, a writer, married with four children, I am back living in the UK. Last year, my son was given a generous bursary at a boarding school in Oxford. A few weeks before he left, the story my father told me came back to me as I wondered how best to prepare him for the inevitable colour-related comments from the more mischievous of his schoolmates.

I called him to my bedroom for a chat. There was no way that I was going to send him to school with my version of “show me your tail”; I had to do more than my parents had done. I did not want to scare him, or make him obsess; I had to get the balance right.

I brought out the notepad that I'd tucked under my pillow and asked him if he was aware of any names that black people were called. One by one, we talked about each one. I took great pains to explain implications of each name. He'd never heard of golliwog, but I told him about it anyway. I told him about the doll and its thick, blood-red lips; its sick, mouth-half-open smile; and its short, permanently-outstretched arms. The more I described the golliwog, the more horrified he looked.

I told him that the image reminded me of the slaves, the “yes massa” tactic that many of them adopted; how they pretended to be docile just to survive. “I will never let anyone call me that,” my son said. I smiled to myself and hoped that his rite of passage would be less painful than mine.

The world has changed a lot in the past 30 years. I was pleasantly surprised that my son had never even heard the word golliwog, which shows just how racially sensitive society has become.

Unlike dark-skinned dolls or black action men, golliwogs, like the black and white minstrels, are a caricature of black features. Without a doubt, this is out of place in a world where we are trying to teach our children to celebrate their differences.

I have no idea what world Carol Thatcher lives in, who she talks to or who her friends are. What I do know is there's something about her that reminds me of all those spoilt, white kids at my boarding school who blurted things - often thinking they were being funny - always without fully considering the effect their words had on other people.

Perhaps they didn't know better, but Carol Thatcher should have.

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