My commitment to you began when you were three weeks old. I said then it was for life, but nobody believed me. Why would they? I was 23, dating a 20-year-old man who was the lone parent of a tiny baby.

People presumed that your teenage mother would want you back. I shielded her from family criticism, from the judgment of people who said that a child should be with his mother, no matter how young the mother, no matter how unwanted that child.

In the absence that became permanent, I insisted that she was right to walk away, if she wanted to; that no mother should have to raise a child she felt unable to care for and did not love.

But I loved you. I loved you from the first feeling of the weight of you in my arms, your first smile. My beautiful, laughing, golden child. I supported your dad to be the father I knew he could be. People said I was wonderful, caring for a child that was not mine. But I was not wonderful, because you were mine. Who else’s could you have been?

You were two when your dad left me. I had no rights. I became a weekend parent. Your world turned upside down. You screamed when I left the room; I even had to take you to the toilet with me. I would sneak out of the house, rather than face goodbyes. It took me two years to feel able to introduce you to my new partner.

I was so worried that you would feel displaced that you were six years old before I felt able to have another child. I still remember your shout of delight when I told you that you were going to have a brother. All my anxieties were unfounded; you were – and still are – a wonderful big brother to both my other children.

People thought that the way I felt about you would change once I became a “real” mother; but I had become a real mother the moment I took you on.

You are a teenager now. You have decided to call me by my name, rather than “Mum”. It felt like a slap. You said it just felt right. “No problem, whatever feels right to you,” I said. That was a lie.

I worry that, as you get older, you will turn your affections to the mother who gave birth to you. It’s so natural to want to seek out your origins. I worry that you will cast me aside. I fear it because you hold part of my heart and you always have.

With all my love, always, your mother.

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