World's Smallest Pony

My REALLY little pony: Einstein, the world's smallest stallion, gets set for first birthday

He may not be able to compete in the Kentucky Derby, but he is surely as popular as the winner.

And with appearances on Oprah and across the U.S. it has certainly been an eventful first year for Einstein, the world's smallest stallion, as he approaches his birthday.

Standing just 20inches tall, the horse attracted huge media interest when he was born in April last year.

Little and large: Regular-sized stallion Playboy stoops down for a closer inspection of his tiny cousin, Einstein

Thousands queued at a farm in Barnstead, New Hampshire for a glimpse of him.

But while human interest was high, he didn't have many friends of his own breed.

Now his quest to find buddies and his life at home with owners Charlie Cantrell and Rachel Wagner in Gilmanton, New Hampshire, will be published in a new a book to celebrate his birthday.

'This has been a remarkable year for us and for Einstein,' said Mr Cantrell, 44, who bought Einstein for their small farm along with his wife Rachel.

'We are both horse enthusiasts and we decided to get ourselves a miniature horse from the renowned breeder Judy Smith at a Miniature Horse Farm in New Hampshire.

Cute: Standing only 20 inches high hasn't stopped Einstein becoming quite a celebrity with appearances on Oprah and across the U.S.

'Einstein is the smallest horse on record ever to survive and when the news got out to the media the level of interest was incredible.

'The average weight of a newborn miniature horse is 18lb. The average height at birth is 21 inches.

Einstein is all the remarkable because he shows no dwarf characteristics and is simply a very small miniature horse.

His mother Finesse stands a relatively tall 32 inches and his dad Painted Feather measures 30 inches.

Little and large: Einstein's stallion friend Playboy towers over him as the pair meet up at home in New Hampshire

Best of friends: Einstein stands alongside Hannah, a St. Bernard he has become buddies with. He also plays with his owner's dog Lilly

'Guinness approached us straight after the original press that surrounded Einstein,' said Mr Cantrell.

'He can't be officially recognised as the smallest stallion until he is four, but we are both relatively sure that he has stopped growing.'

With the press surrounding him, it wasn't long before Einstein did make friends - of all shapes and sizes.

He now spends his time mingling with his giant friend Playboy - a full sized stallion - and messing around with Charlie and Rachel's dog Lilly.

'Playboy is owned by a young lady who lives next to our farm and Einstein sometimes meets him to have a head sniff and a simple hello,' explained Charlie

'You see the adorable thing about Einstein is that he doesn't seem to be too aware of his height at all.

'He approaches Lilly and Playboy just like he was a fully grown stallion. He rears up and huffs and gallops around.

'However, due to his extraordinary size he can't mingle around with other horses because it would be dangerous and he might get trampled underfoot.

Having a ball: Einstein is even smaller than a football but that doesn't stop him using his nose to push the ball around

'So him and Lilly kiss and say hello, he knows a particularly friendly St Bernard at the farm he was born at and we have a couple of Nigerian Dwarf Goats that he spends time with here in New Hampshire.'

Living peacefully in his own pen on his owners land, Einstein's first birthday is something that GP Rachel and Charlie can't wait to share.

'He loves children and they of course love him,' said Charlie.

'They get wide eyed because they have never seen a horse this size before and they want to smother him.

'However, he is so small, so hopefully the book will satisfy everyone's desire to see Einstein and his cute and unusual life.'