Hugh Johnson for the Guardian

The siblings of those with anorexia or other eating disorders are often overlooked. The UK’s leading eating disorder charity, Beat, has described siblings as the “forgotten victims”. In one report on the charity’s website, eight teenagers with anorexic sisters were interviewed about their experiences. All were negatively affected, even though they also sympathised with their sisters and knew that the illness was not their fault. Many of the siblings felt the eating disorder affected every aspect of family life. Each developed personal coping mechanisms. Some tried to pretend it wasn’t happening. Others found themselves talking about it obsessively. Some distanced themselves from their sister, but others became closer, often assuming an almost parental role.

When one person at the table radically changes the way they eat, the whole ecosystem of a family has to adjust. A meal is not the same thing when it is not shared. I wish I had understood better as a teenager how entangled eating behaviour between siblings was. My sister wasn’t to blame for my problems with eating; but it was only when she became ill that it was obvious how much my apparently robust appetite took its cue from her. Numerous studies confirm that peers have a very powerful effect on how a child eats. Under the influence of those who share our childhood meals, we may eat faster or slower; take a bigger or smaller portion; eat breakfast or not. The effect is stronger if that person is closely related to us; stronger still if we love them.

At school, I had a new best friend, who ended up at the same university as me. Like my sister, she suffered from anorexia. Once more, I was the chubby one in the relationship; the normal one; the one who supposedly didn’t have a problem. Unlike my sister, my friend didn’t mind talking to me about her deep unhappiness with food – and other things – as she sat, pale and thin on the floor of her college room. This time, I felt I could help, although listening to her was also, selfishly, a way for me to play out my own obsession with food. I hung off her every word as she told me how upset she was when a boyfriend gave her a cup of tea and she could taste the greasy fat in it from a splash of whole milk. We went to the cinema, and whipped ourselves into shared paranoia that the person behind the counter had given us regular sugary Coke instead of Diet. In private, I still binged, and despised myself for it, but when I was with her, I tried to emulate her ways of eating. Unlike me, she was so beautiful and so thin.

– Bee Wilson

Read more: ‘At first, she just missed breakfast’: living with my sister’s eating disorder