Martin Kemp has three kidneys.
The 56-year-old actor and singer made the bizarre confession during an appeared on ITV's 'Loose Women', in which he joked about stealing the kidney of his older brother and Spandau Ballet bandmate Gary, who only has one such organ.
The former 'EastEnders' star confessed: "I have got two big ones and one tiny, small one, but what's really odd about it is that my brother, who is two years apart, only had one.
"I went for an X-ray one day and they were doing a medical and said 'you've an extra one' and I said 'well, that's my brother's!'"
It is common for most people to be born with two kidneys, but it is possible to survive with just one.
However, Martin admitted that the extra organ - which helps the body to filter out alcohol from the blood - didn't stop him from feeling the impact of a wild night out.
But the British star doesn't suffer with hangovers any more since he no longer drinks alcohol.
He said: "I used to get big hangovers, that's a fallacy, but I don't drink anymore which is really nice, I stopped drinking years ago."
Meanwhile, Martin's 25-year-old son Roman Kemp recently insisted he won't be following in his dad's footsteps by appearing in 'EastEnders'.
The DJ harbours dreams to make it big on the big and small screens at some point, but has ruled out appearing in the long-running soap.
Roman - who is best known for working on the Capital FM radio station - told BANG Showbiz: "I wouldn't do soaps. I would do acting 100 per cent, I love acting.
"I don't see myself on Albert Square anytime soon."