India, May 5 -- In a rare and medically documented case, twin sisters in the United Kingdom have discovered in their late 40s that they do not share the same father. Michelle and Lavinia Osbourne, 49, born minutes apart in Nottingham in 1976, learnt the truth after taking at-home DNA tests decades later.

The results showed that while they have the same mother, they are biologically half-sisters - a condition known as heteropaternal superfecundation. The phenomenon occurs when a woman releases more than one egg during a cycle and each is fertilised by sperm from different men. Fewer than two dozen such cases have been identified globally, and this is believed to be the only documented instance in the UK, according to a report by BBC.

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