My daughter Amy Reyes, who has died aged 17, was unable to talk – but she could communicate. She could let us know of her excitement at a familiar piece of piano music; her enjoyment of the sweariest of Lily Allen’s songs; her approval of particular people and boredom with others; her dislike of getting out of bed on cold dark mornings; her disdain for anything she deemed too try-hard. She was extraordinary.

Her life was made hard by Rett syndrome, the neurological disorder she was diagnosed with shortly before her second birthday. It caused havoc with her brain and body. But her essential Amy-ness always shone through. She was a girl who loved music above all things, especially the piano. Sitting beside her father, Eduardo, as he played, her face would light up with joy. We were certain that, if her hands had worked, she would have been a pianist herself.

Amy did not suffer fools. She would turn her head away from anyone who talked to her in a baby voice or who tried to manufacture enthusiasm on her part. No one could make her do anything, and she could not pretend to be anything other than what she was. This was what made her such a wonderful, authentic person. When Amy liked you and gave you her attention, you knew she absolutely meant it.

She loved her family, but that did not mean she always wanted to be with us. Going to school was the central part of her life – from the age of three, when she started attending Cherry Garden, a very special primary school in Peckham, south London. She moved on to the nearby Tuke school at 11, and thrived there on the routine, the fun and the expectation that every child could be involved in every part of school life.

Amy changed our lives as a family, and not just in the obvious ways. Slowing down to make the world work better for her made it work better for us too, as we took time to appreciate the things that Amy liked. She had an excellent sense of humour, and a highly developed sense of the absurd, which got her through so much tough stuff, including major surgeries and endless appointments at St Thomas’ hospital, where she was born and where she died.

It is a cliche to say that she taught us more than we taught her, but she really did.

She is survived by me, her father, Eduardo, and her sister, Abby.