Strangely enough, Daniel’s wedding day didn’t upset me at all. It was his 30th birthday six months later which really got to me, as he stood there with his wife Alison while they greeted the guests. I can honestly say that that was the only time when I felt real envy and wished desperately that it was me standing beside him, arms round each other as we showed the world how much we loved each other.

It’s not as if I’m not allowed to love Daniel, but the way we feel about each other isn’t something that we can share easily with anyone else. Daniel is my brother, but since I was 14 we’ve had a sexual relationship - and that’s not something that many people would feel comfortable with.

[…] While I was still at university a friend had a major misunderstanding with a relatively new boyfriend when one of his friends had reported back to him that he’d seen her hugging and kissing another man in the union bar. She […] became […] exasperated when she explained that the man in question was her brother […]. Their loud discussion took place in the union with an interested audience, until he finally stamped out in fury, still refusing to believe her. As she flounced back to join us she made a remark about preferring her brother to any other man, whereupon one of the crowd said “Yuck, how pervy!” As she sat down beside me she muttered something like “It’s not that strange,” and three or four drinks later I quietly asked her what she’d meant.

Fuelled by drink or maybe just rage, she started talking in a very intense but hushed way about how close siblings could be, going on to say that she was sure that many people experimented sexually with them as they grew up and then simply grew out of it. She said it was like practising your social skills on your family and so long as it was mutual, she couldn’t see the harm. I didn’t say much - partly because I couldn’t believe that I’d met someone who seemed to be like me - and she very quickly clammed up and moved over to talk to someone else and never brought up the subject again.