Lynn Walcott apologises for the gentle mayhem amid tea and hospitality. It's like Piccadilly Circus at rush hour. The three dogs of the house are bounding around barmily, her nearest and dearest are flitting busily between rooms, landscapers have turned the back garden into a building site and the driveway is blocked by four big motors.

A fifth guzzler is leaving as we arrive. It is the place's teenage millionaire owner escaping in his 4x4 to football training. "We've always lived in complete chaos. It's just the way we are," says Lynn. "But Theo is different to us; he likes order, tidiness and cleanliness, so all of us drive him nuts. He has to nag us, constantly tidying up behind us."

She smiles at how things have changed. The family are still as close a unit as ever but now Mr Theo Walcott is not under their scatty roof; they're under his ordered one: Lynn, dad Don, brother Ashley and girlfriend Mel, plus sister Hollie who is over most weekends with her lot. This is the five-bedroom house in Hertfordshire which Theo bought in the summer he became England's youngest-ever international and it is the sanctuary he was determined they would all share.

Not two years have passed since that crazy spell when a boy barely turned 17, who had not played a Premier League game with Arsenal, was gobsmacked to learn he was off to the World Cup.

Even though he never played him in Germany, Sven-Goran Eriksson created a hell of a burning spotlight for any kid to have to deal with. How well has he coped? Some say he is too lightweight, that he's not progressed quickly enough, that, as David Bentley suggested, he needs to leave Arsenal to further his opportunities.

Others, perhaps including Fabio Capello, who seems set to recall him for next week's friendly in France, have seen his recent electric cameos and still recognise a potential diamond for England. Then there are those, like Walcott's dad, who just remind everyone of the only salient fact: "Look, he's not even out of his teens yet."

Theo seems to have been around for so long you forget he was only 19 last Sunday. His birthday celebrations? Hitting a few golf balls, a quiet lunch out and then go-karting. All with the family, naturally.

Because Walcott doesn't do wild champagne nights out. Lynn laughs that Theo, chuffed with how he features in the Arsenal version of Monopoly (he's the club's answer to Leicester Square) is happier with a night in playing board games.

It sounds like there is still something of the wide-eyed innocent about him. Don tells comically what happened after the first leg of the recent Champions League tie against AC Milan.

"Normally, he takes his time but this night, he just zoomed off. When I asked him why, he said he had to get Kaka's shirt before anyone else did."

He did, too. And got it signed. A fortnight later, after shooting past the Brazilian in the San Siro, he phoned with the declaration: "Did you see it, dad? I did Kaka!" Meeting this smashing couple, you understand where his level-headedness comes from.

Lynn, an independent midwife, reckons her greatest contribution to Theo's footballing development was to pass on the "laid back" genes which enable him to treat criticism with a shrug.

The "emotional, competitive fire" in him, she says, comes from Don, a former RAF administrator who runs a company promoting his lad. They make him sound the perfect son.

"You wouldn't believe how generous he is," says Lynn. "He could already have his nest egg if he hadn't lavished it on his family." He has bought them all expensive cars and a private box at Emirates Stadium. After one comment about how she'd love to learn to play the harp, Lynn was amazed to find a £2,500 Welsh harp sitting on the doorstep come Mother's Day.

Theo feels happier when the family are around. Yet Lynn believes it is Theo's own independent, "instinctual" streak which will serve him best. "He's always been singular in his opinions, he knew his own mind," she says, showing off a photo to illustrate her point.

It is of a 12-year-old ball boy standing beside Michael Owen before a Chelsea-Liverpool game. Chelsea had tried to woo the kid who had scored 100 goals in a season for AFC Newbury by inviting the Liverpool fan and his dad down to Stamford Bridge. "He met his hero, had a lovely day out and they showed him round this fabulous place," recalls Lynn.

"But then Southampton took him to their training ground when nobody was there, showed him the boot room, and he just decided, 'This is where I want to come'. He just said Southampton felt right; he's not influenced by people."

Five years later, when it was time for his next move after Southampton, he again turned down Chelsea among others, this time for Arsenal. So, when he returns to Stamford Bridge for the crunch Premiership clash on Sunday, what odds on him making the Blues really rue the kid who got away?

Because you get the feeling Walcott's time may be arriving. His dad added: "The thing about him is that if anyone ever writes him off, he'll fight and always prove them wrong."

In Theo's castle, you wouldn't want to play him at Monopoly.

• Lynn Walcott is supporting McDonald's Mums On The Ball campaign to encourage more mothers to get into grassroots football coaching.

Visit www.mcdonalds.co.uk for more information.