I've never made this mistake, but I think the odds of it happening are probably higher than you might think. On the other hand, perhaps it's a viable option with no taboos attached? Would you ever date a man and then move onto his brother, just in case his parents had better luck that time?

A few years ago when I had just moved to London, my friends and I used to go to the same funk night every Friday – the funk phenomenon – in a bar in South London. One night, a friend of my brother's, Alex, turned up. He quickly caught the eye of my friend Alice. The usual flirtation, dancing and eventual exchange of numbers took place and before long they were 'seeing each other.' Unfortunately, as with so many of these things, it didn't last long.

A few months later on a dragging Friday afternoon at work, I was exchanging e-mails with Alice about the night ahead when she told me she was going to bring her new fellah along. His name was Jones - because people used his surname as his first name - and he was a bit younger then her, but really cute (she said) and would be a laugh. Alice had met him at her job where he'd recently started and she'd made sure she got her hands on him before anyone else.

When I arrived at the bar that night, Alice was sitting with her new man. I couldn't get near to them for a while as there was such a big group of us and I was desperate for a drink, but we were eventually introduced. He was cute and very nice, but there was something about him…suddenly it dawned on me. I'd seen those puppy dog eyes before somewhere - could it be?

I toyed with how best to break the news and, all of a sudden, I blurted it our before thinking it through.

"Alice," I said, with conviction, "meet Jones, Stan Jones, Alex Jones' little brother."

The look on her face - total shock and disbelief - while poor Stan didn't know what was going on and smiled sheepishly.

That relationship didn't last long. Alice said she couldn't stop thinking about Alex when she was with Stan, comparing the two and feeling a bit incestuous.

She'd really had a lucky escape. Apparently earlier that week she'd been to Stan's house for dinner with his parents, but his brother had been out. We imagined what Alex would have said if he'd walked into his living room and found her kissing his little brother.

And as for the brothers? I guess they felt a little strange too. After all, there are some things brothers, however close, perhaps shouldn't share.