When Adam Hargreaves was six, he asked his father, over the breakfast table, a question. The answer would prove to be a defining moment not just for them, but for millions of children around the world.

Because little Adam's father was Roger Hargreaves – the creator of the Mr Men and Little Miss books. Which, this year, just to make many of us feel very old, celebrates its 50th anniversary.

"I was too young to remember it," Adam tells KentOnline of that defining moment in his life. "But I asked my dad one of those impossible questions little children do to test their parents with – and mine was 'what does a tickle look like?'"

His father, then a creative director at a leading advertising agency, sketched a sight now familiar the world over. Long, spaghetti-like arms and that trademark top hat. Just like a tickle should look, in fact.

"I think that sparked off a chain of thought in my dad, that you could personify a human emotion or characteristic," Adam explains.

"I think he could see suddenly that he could turn Mr Tickle into a character and then write a story about it. And if you could do a tickle you could do all the other emotions."

In August 1971, Messrs Tickle, Greedy, Sneezy, Bump and Nosey appeared on bookshelves for the first time. Within three years, they had sold a million copies. With many other characters and sales to soon follow.

It would take the Hargreaves family on a remarkable journey which would culminate in them moving, in 1982, into a sprawling Grade II*-listed farmhouse, complete with 220 acres of working farm (primarily beef and arable in case you were wondering), in the village of Cowden, in the Sevenoaks district, and sat on the Kent and East Sussex border.

It was a clear sign of the wealth the family had amassed due to the phenomenon Roger had created. When the house was put on the market three years ago, it carried a £5.5 million price tag.

But it was also there that tragedy would forever change their lives in a way no one could have imagined.

"During the 1970s my dad became a wealthy man," explains Adam. "And he enjoyed his success. One of those perks was a very nice house."

Father-of-four Roger had long harboured ambitions of quitting his job in London and giving up the commute.

He had a long-held ambition to draw a comic-strip, wanting to emulate the likes of Snoopy and Charlie Brown in Charles Schultz's Peanuts cartoons.

"He was a larger than life character in all respects," Adam says of his father. "He was 6ft 5in, so very tall and commanded a room. He was really rather ebullient, and had a terrific sense of humour, that I think comes out in the stories. He loved puns, practical jokes and daft humour. But he was a hard worker, and spent a lot of time creating the success of the Mr Men.

"When he was in advertising I didn't see him all week long, because he would get home after I'd gone to bed. So it was nice when the Mr Men came along, and I think it was 1975 he stopped advertising, and was home a lot more. And that was lovely."

But as the books took off, for Adam it proved more of a millstone around his neck during what he describes as his "awkward" teenage years.

"I was very shy, so I shied away with having any connection with the Mr Men," he explains. "I didn't like anything which drew attention to myself so I tended to try and ignore it. It did embarrass me rather."

It was not helped by the fact that Roger Hargreaves was rather pioneering when it came to merchandising – blazing a trail for products and goods which would bear his creation in a way which would be capitalised upon by the likes of the original Star Wars movie just a few short years later.

Adds Adam: "Coming up with ideas for new products and packaging was as exciting for my dad as actually writing the new books and creating stories."

For that shy teen, there was no escaping his father's creation.

Many will remember the BBC TV show of the 1970s – voiced by Arthur Lowe, better known as portraying Captain Mainwaring in Dad's Army – which seemed to form part of children's TV programming for years.

"I regret the way I felt now as, because my dad died so young, I didn't get to tell him how I felt about Mr Men and what a brilliant idea I think it is," says Adam.

The Hargreaves family was hit by a devastating blow in September 1988.

After suffering a stroke, Roger Hargreaves died at the Kent and Sussex Hospital in Tunbridge Wells. He was just 53.

"My mum stayed at the farmhouse and I took over the management of the farm for a few years after he died," explains Adam.

"So I was doing farming and handling the Mr Men business straight after my dad died. My mum stayed there until about 1992 and then she sold the farm."

Adam would continue to live nearby – moving to Tunbridge Wells and Langton Green for many years, before hopping across the East Sussex border to Heathfield, where he lives today.

While they looked to keep the Mr Men series alive in the hearts and minds of the new generation, in 2004 the family agreed to sell the rights to UK entertainment group Chorion in a deal worth £28m.

Seven years later, they were sold to Japanese firm Sanrio.

And it guards the family well. It has taken almost 11 months of patient negotiations and regular reminders to organise the interview with Adam.

"I still think it was the right decision," he says of the decision to sell. "I think for the Mr Men to be owned by one family without the kind of investment that a multi-national company has was going to mean Mr Men would dwindle to a degree and never quite reach its further potential in the future. That was one of the principle reasons for selling. Obviously we got a good offer as well.

"From a personal point of view I've been very happy with the fact I'm just involved in the creative side and I don't have to worry about trademarks and copyrights and business contracts and that sort of thing."

And the family connection remains strong.

Having studied art, Adam Hargreaves was persuaded to follow in his father's footsteps. He started creating new characters and stories – something he continues to this day for publishers Farshore.

His creations include the likes of Mr Calm, Mr Cool and Mr Good.

Interestingly, he always insisted his father's name appeared on all his books.

He explains: "I felt quite strongly about it, especially when I first started writing the stories. I felt they were my dad's. Since the 1990s when I first started writing the books, his name has become part of the brand. Now it's a dual thing – me, for not wanting to take credit for the idea, and also it's part of the brand strength.

"What would he have made of it 50 years on? He would have been very chuffed – tickled pink would be the phrase. And probably rather pleased with himself too, as he did enjoy the success and the degree of fame that came with it. He was creatively ambitious.

"He enjoyed the business side of it. The creation of a brand, as it were. As well as simple children's book idea."

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