If you stand by the gate of Moor Lodge Farm you can see a hand-written sign on the back of a little home-made wooden trailer attached to a toddler-sized tractor: “Philip Mellin farmer”, it reads. The tractor is the only sign that there’s a child within.

The farm consists of a small stone bungalow which overlooks Wolfstones Moor, a wild, stonewalled heath above Haworth - the heart of the Bront s’ Yorkshire - that takes in 170 acres, where 500 Swaledale sheep are tended by Albert and Carol Mellin. Philip is their three-year-old son - and he’s a kind of genius.

At 18 months, he took to the shepherd’s whistle that hung around his mother’s neck and could soon blow it as well as any adult shepherd. With uncanny accuracy he can now produce the sounds required to run a dog for herding sheep: two high pitched tones for a left turn with the cry “Come by”; for a right he’ll give a high, low and a high and holler “Away to me”; then comes the continuous long whistle from high to low for “Lie down” and two short whistles with the call “Steady!” for walk.

Nell, his mother’s dog, will take 50 per cent of his calls, but she won’t even walk for his father. It’s a skill that’s hard to acquire and some adults never manage it, but Philip is in his element out in all weathers with Nell, sounding his whistle. His childish “Ho! Ho! Ho!” and pips on the Land-Rover horn, calling the sheep, travel across the windy moor.

It is quaint to see Philip, a mere 3ft 4ins, wearing a flat cap and waistcoat, the correct dress for attending the livestock markets and sheepdog trials frequented by his parents. The ginger-haired lad is in earnest. Shepherding is his obsession, and if he can’t be doing that he’ll be out in the milking parlour yard moving the cows and the Mellins’ immense, lumbering Charollais bull with a gruff “Gerrawn!”, shovelling muck, or forking the silage.

Earlier this year Philip stunned the crowds at a Lancashire sheepdog trial after begging the judge to let him take part. His mother says: “The judge agreed to let him go on while they sorted out the results. He put on his flat cap, got his stick and penned them up.”

Philip will even stand in the ring showing his parents’ lambs at auction. This little boy knows when a bid’s accepted and which gate to send them through. When the family returns from these sales at Skipton market, some 15 miles away, he’ll direct his father home. A child of few words and unclear diction, he’ll nevertheless give you one thing straight: he wants to be a farmer.

The Mellins have worked this land for generations. Albert Mellin, a 60-year-old tenant farmer, is awestruck by the precocity of his son. He calls him “little man” and is proud of his talent. He says: “When he’s out with the sheep he positions himself just right. You don’t have to ask him to do anything. He just seems to know what to do. He’s allus watching, allus helping. He’ll work till he sweats. He can pick his own sheep out, he can pick out the tups (rams) an’ all. I know lads of 11 that can’t do that.

“We had a chap brought in some bantam cocks. Philip can clean the feathers off as well as me. He can clean out pheasant too. We’ve never worried about ‘im workin’ wi’ a penknife. He just gets up on the sink and pulls out the intestines. He knows which is the heart, the kidneys.”

Philip is nearly four and will be starting school in September. He already attends Oldfield Primary, two miles away, one morning a week. According to his father, he’s “as happy as King Dick” there. His parents are keen for his education to develop, but believe that as their constant companion since the day he was born, he leads a privileged life - not in financial terms, because as small hill farmers they struggle desperately - but because he has already learnt an astonishing amount. “He knows a lot of natural stuff,” says his mother.

Amazing as they are, Philip’s abilities are not inexplicable. His mother, Carol, aged 39, is addicted to the farming life. Born and brought up in nearby Oxenhope, she has farmed for most of her life, but only took to shepherding five years ago when she met Albert. Now she is a dedicated shepherdess, accompanying her husband every minute of the working day, and wins more trophies at sheepdog trials than he does.

Two years ago, she was the first woman to win the coveted first prize at the Pennine Association Inter-Club Championship, the biggest regional event of the winter season. Albert is proud of her. “People running dogs for 20 years haven’t won prizes like she has,” he says. “She’s got real sheep sense.”

Wherever Carol goes, Philip follows, even to the “endless funerals” of the older generation of sheepdog-trial men that she and Albert attend. “He’s always quiet at those,” she says, “watching everything; he just senses the atmosphere.” Carol and Albert work their land unaided, so if she is out dry-stonewalling, Philip’s out doing it as well, filling up the middle with the smaller stones. “Yesterday, Philip and I were out in the Land-Rover on our way to do some walling, but first I had to find a hog (last year’s lamb),” says Carol. “He just said: ‘Drop me off - I’ll make a start.’ When I came back 10 minutes later, there he was, head down, bum up, just getting on with it.”

The only television Philip wants to watch is, perhaps not surprisingly, One Man and His Dog, though Carol notes that he has recently taken to the Teletubbies. Few toys are in evidence around the tiny rooms of the bungalow, and, while the adults talk, Philip seems content to push a lone toy tractor around, simulating some fairly sophisticated engine noises.

Every day, the family rises at about 7am. Albert puts the kettle on. Then Carol and Philip sit on the sofa and drink tea - he takes his from a feeder cup and has done so since he was six months old. While his parents are out milking, Philip might lay the fire, raking out the ashes, putting on the sticks and then dress himself, zipping up his anorak, folding his trousers into his wellies, then join them outside in the cow sheds. He’s an independent little boy.

They come back for a cooked breakfast - eggs from the farm, “proper” dry-cured bacon, “all fat as it should be”, that’s kept, hanging up, in the Mellins’ bedroom. For the rest of the day Philip accompanies his mother about her work.

The Mellins live a largely subsistence life, eating from the farm, taking pheasant and rabbit off the hills. Albert reckons they spend no more than pound;25 a week on bread and groceries. They go to the supermarket once a year - at Christmas. Carol says they don’t spend money on clothes - all of Philip’s are passed on by friends and neighbours. She says: “We have a different way of life to everybody else. We haven’t got a lot of money, and we don’t own the farm. There must be easier ways to make a living. You either love it or you hate it, and if you hate it you get out.

“But it is a privileged life. Philip is learning to care for living things, not just computers and the telly. When you go out on the moors you can’t be closer to heaven. You’ve got the grouse and the skylarks. I’m not romantic, but it does get to you. You never know what the weather’s going to bring, and that’s a challenge.

“This is the kind of job you want to do until the day you die.”