There was a surprise in store when Denise Harrison cracked open her egg - another, tiny egg nested inside it.

Mum-of-three Denise was making a family-sized omelette for her own peckish brood when she made the amazing discovery.

She bought the six-pack of eggs from Tastables fruit and vegetable shop in Preston Park, Brighton.

As she cracked open the fourth egg in the box she was shocked to find a second smaller egg, with a soft shell, tucked in the middle.

Denise, of Ditchling Rise, Brighton, carefully prised open the duplicate egg and found a perfect yolk, about the size of a penny, which she has kept on a plate in her fridge.

Denise, 37, said: "I have heard of double yolks before, which are twins presumably, but it is the first time I have come across this.

"Now we have this cute little thing in the fridge that looks like the smallest fried egg in the world and we are not sure what to do about it."

Daughter Poppy, three, was equally amazed by the discovery.

She said: "It's little - just like me."

Dr Martyn Stenning, a tutor at Sussex University, said the egg was just one of nature's oddities.

He said: "It sounds like a double yolk egg that went wrong and was actually forming as a second egg inside the original egg.

"You probably get quirks like this all the time but farmers usually only send good eggs, so to speak, to the supermarket."