Twins who were born five years apart

That is because, despite the fact the brother and sister were conceived from the same batch of embryos, they were born five years apart to parents Simon and Jody Blake.

Mr Blake, 45, and his 38-year-old wife had been trying to start a family without success and began fertility treatment in 2005.

During the medical process, five embryos were created and two implanted in Mrs Blake, which resulted in the birth of Reuben on December 9 2006. The remaining three embryos were frozen until the couple, from Cheltenham, Gloucestershire, decided to try for another child last year.

Against the odds, Floren arrived on November 16 2011 – two weeks before her due date – but five years after her twin brother.

“I tell everybody I can,” said Mr Blake. “Just in kind of mundane settings where people take an interest in a newborn baby and with Reuben around as well, I find it very difficult to resist the temptation to say ‘Oh and by the way they are twins’.

“It’s almost just to see people’s response. They are really amazed and surprised.”

His wife, who works for charity WellChild, said: “It does feel quite surreal. I think people are really, really surprised and it almost takes people a few minutes to get their heads around it.

Reuben is said to have quickly settled into his new role as big brother to his own twin sister.