Almost 30 years ago, you exploded into our lives. Exploded is an appropriate term because we had no warning about your condition. It is fair to say that I was devastated. I felt I had been catapulted into a world in which I did not want to belong.

My early memories of that time are painful. I remember a nursing assistant in the hospital picking you up from your cot without permission and announcing, “Ooh, I love Down’s babies!” Well-wishers looked at me pitifully as they asked, “Didn’t you have the test?”

They were dark times and it was not an easy transition, but your older sister, who was two when you were born, welcomed and adored you. Your younger brother was born two years later and then, after three more years, there was another sister for you. Family life was chaotic. There were a lot of fun times, but also embarrassment and frustration, such as the time you took off your clothes in a department store, or flushed your sister’s makeup down the toilet.

Your learning disability is such that you have no spontaneous language and require 24-hour supervision and support. Your additional needs demand a rigid structure and routine.

Your brother and sisters have now grown up and live in their own homes. Your dad and I got divorced, an unfortunate casualty, in part, of the pressures of raising a disabled child. You are living with me, still enjoying Postman Pat and Disney.

I wonder how you make sense of all the changes? I know your quiet acceptance masks a much deeper understanding of human nature than any of us could hope to achieve. Your dad and I enjoy a good relationship now and he continues to be a big part of your life. Your siblings are always popping in for an audience, and an essential hug from you. You say little, but your presence is immense. You are their counsellor and their mentor. For them, you reinforce the essential simplicities of life, things we often lose in the chaos and mundanity of everyday existence.

The positive contribution you have brought to our lives is immeasurable, and that extra chromosome I so despised in the early days of your life is now revered, with gratitude, as an integral feature of the wonderful person to whom it belongs: you.

You are the glue that binds our unique, amazing family together. I feel privileged to be your mum.

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