When DNA test results shattered everything Lavinia and Michelle thought they knew about their family history, they also revealed something never before documented in the UK

I like being a twin. It defines who I am,” Lavinia Osbourne tells me on the 49th birthday she shares with her sister, Michelle. “It’s amazing to have a twin and have a built-in friend for ever,” Michelle says. “I’ve been really blessed to go through this journey with someone else.”

Lavinia and Michelle know that those of us who haven’t shared a womb with a sibling can be fascinated by twins: their similarities, how they differ, whether there’s any kind of mysterious synergy between them.