They call him Dylan, and with his mop of blond hair and winning smile he should be the apple of his mother's eye. Except that he has no mother, or father, or brothers and sisters. No one claims him as their own. He has no date of birth and no birth certificate. He has no birthday. Even his name is not his own.

Sometime in the early hours of 6 June, Dylan was abandoned on a remote lane in Colwyn Bay on the North Wales coast. After laying him down among the leaves and litter, someone turned and walked out of his life. Most babies are abandoned where they will be found quickly. Dylan was not.

Recorded life for Dylan began some hours later when, almost hypothermic, he was discovered by a man out walking his dog. Later he was given the name of the ambulance drivers who took him to hospital: both were called Dylan.

After five months, North Wales Police are no nearer to finding his mother. Nobody has come forward to identify him as their son, or even grandson or nephew. Like an RSPCA stray, Dylan has no history before 6 June.

Now, as late autumn sun streams through the windows of a seaside town house, not far from where he was found, a chubby-faced boy is motoring around in a baby-walker. "He can only go backwards," laughs Pam, his softly spoken foster mum, a motherly woman with grandchildren of her own, as she gets up for the umpteenth time to turn him round.

Behind her a sideboard is full of photographs of the dozens of children she and her husband, Ted, have fostered over the years.

One picture stands out from the rest. It shows a thin gaunt baby, all cheek bones and shadowy, staring eyes. It is hard to believe that this is the same baby as the picture of health in the baby-walker. Now in their fifties, Pam and Ted are experienced pre-adoption foster parents, and have fostered 12 babies, but none were as undernourished as Dylan when he arrived.

"I have never seen a baby so pale; his skin was almost see-through," says Pam. "I don't think he had ever been outside at all. When we first saw him we just cried." Dylan, though, shed no tears in the first week. "It had probably got him nowhere in the past," says Pam. "Most babies cry because they want something and it obviously hadn't worked for him."

Doctors now think he was born in the first week of March. When he was first discovered, and the veins in his stick-like arms collapsed as they tried to take blood samples, they could only hazard a guess.

If his mother does not come forward, Clwyd social services fostering and adoption officer, Rosemary Walker, will have the job of naming Dylan's birth date for his birth certificate. Among Dylan's "life things", collected to establish some personal history, are cards and toys from well-wishers, including a teddy from baby Lydia Owen, of Llandudno, who was snatched from hospital by a woman desperate for a child.

What concerns Ms Walker is how Dylan will come to terms with this huge gap in his history as he grows older.

"It is extremely hard for adopters to explain, because abandonment is real rejection," she says. "It is just a brick wall, a dead-end. This child will go through life knowing that someone threw him away and didn't care enough to choose what happened to him."