A four-year-old girl has become the UK's second youngest member of Mensa - making her an official genius.

Little Alannah George recorded an incredible IQ score of 140, earning her way into the elite group.

The reception class pupil, from Iver, Buckinghamshire, is 'obsessed' with words and numbers and taught herself how to read before ever stepping foot in a classroom.

Her parents said from early on she would rather recite the alphabet and times tables than singing nursery rhymes.

Her incredible IQ score means she's of 'superior general intelligence'. 

Mensa is an of the most intelligent 2 per cent of people in their age group - and entry to it is strictly marshaled.

The average adult has an IQ of 100, while Professor Hawking and Professor Einstein are thought to have an IQ of 160 although they are not known to have sat tests. 

Alannah officially became one of the youngest members of Mensa in the world last month, and her parents, Nadine, 37, and Edmund, 39, said it was a 'scary' realisation.

'It's exciting and overwhelming. I want to make sure she achieves her potential and manages to perform to the best of her ability,' said Nadine.

'She is so young but she lives and breathes academia. It was a scary realisation when we got the results about how clever she is.

'She is coming on leaps and bounds. She has got an aptitude for reading and can decode words herself.

'Alannah was always very alert as a child. We never taught her how to read she just did it on her own.

'She is clearly special but we just don't know what her potential could be.' 

Alannah who has been exceeding expectations since she was tiny now goes to the same school three of the Queen's grandchildren once attended.

She is a pupil at the prestigious St George's School, in Windsor Castle, which was once attended by Princess Eugenie and the son and daughter of the The Earl of Wessex.

But she is already miles ahead of her current classmates. 

Last month she was assessed by top educational psychologist, Dr Peter Congdon, who said Alannah is an 'intellectual genius'.

Alannah was born in August 2014 and uttered her first words at just seven months old.

By the time she was 18 months old she was able to speak in full sentences and when in nursery, aged three, Alannah could read full paragraphs from some of her favourite story books.

She can now 'read herself bedtime stories' according to Nadine, who also has a son, Ethan, aged two, and is married to management consultant, Edmund, 39.

And unlike your average four-year-old, who might watch Peppa Pig or Dennis The Menace, Alannah likes to watch a show called Endless Numbers on YouTube.

It was as early as when Alannah was just a toddler, aged one, mother, Nadine, began to realise brainy Alannah was a 'special child'.

She said: 'She reached all of her childhood milestones way ahead of time.

'She was always very alert and taught herself how to read before she was three.

'Alannah was my first child but I knew she was passing milestones way earlier than usual.

'As a first-time mum it was all new for me. But at 18 months she was reciting numbers and letters form nursery rhymes and when she was two she knew most words.

'We used to read a lot of story books together and she just picked up reading on her own. She learnt herself before even going to school.

'By the time she was two she was coming on leaps and bounds. It was the reading that freaked me out a bit to be honest.'

Having recognised Alannah's special talent, business analyst, Nadine, sent her for an assessment with Dr Congdon, in January, who gave her official 'genius' status.

He put her through the rigorous Wechsler Preschool and Primary Scale of Intelligence test - which tested Alannah's problem solving capabilities.

She was made to answer a number of question and was given an IQ score based on her results.

An average age-specific IQ is 100 and typically around 60 per cent of the population score between 85 and 115.

The test also gave Alannah the reading age of a seven-year-old and the spelling and mental arrhythmia age of a child aged six-and-a-half.

Just a month after sitting those tests, Alannah was accepted into the exclusive Mensa club and is now recognised as a 'gifted and talented child'.

Nadine is confident her super-smart daughter has a bright future ahead of her and is determined to support Alannah to achieve her potential.

Because of how clever Alannah is, her teachers are planning on adapting the school curriculum to meet the standard she is working at.

One worry for both Dr Congdon and Nadine, is that due to her higher intelligence, Alannah could become 'bored' by lessons aimed at regular four-year-olds.

In his report, Dr Congdon says she is at risk of 'under-achieving'.

The report said: 'Alannah will benefit from being challenged and stretched in the school situation otherwise she may become prone to boredom, frustration and under-achieved.'

He does admit, however, that Alannah sometimes gives the impression of being an 'introvert' and Nadine says she hopes her daughter's 'shyness' won't hold her back.

She said: 'She's a very quiet girl and observes things without necessarily showing she is capable.

'She is very reserved and may not show all of her abilities all of the time.

'Dr Congdon was very impressed and said he felt her score could be higher. He wants to see her again in three years time because some aspects of her abilities could be better.

'I want to give her the opportunity to achieve her potential. She needs to be stretched. Her curriculum needs to be altered so she doesn't get bored in class.

'She is still so young and I want to make sure she has an enriched childhood. But she lives and breathes academia.'

Nadine added she would consider entering Alannah into Channel 4's Child Genius show, if she shows an interest in taking part.

But the main thing for Nadine is to make sure Alannah lives a 'fulfilled and happy' life and enjoys being a child like every other youngster.

She said: 'I just want to make sure she reaches her full potential and is happy. That's the main goal.

'I am in no way a pushy parent so we will support her with whatever she does.

'We always knew she was advanced but we were so shocked with the results. We never knew she was that intelligent.

'She is very energetic and needs little sleep and I know that's a characteristic of intelligent children.

'We do hope she comes out of her shell a bit. Hopefully school will help with that.'

Alannah will start academic education in September, when she joins year one at St George's School. 

In 2009 Elise Tan-Roberts - aged two years, four months and two weeks - became the youngest person to join Mensa UK.