Christmas cards piled up on his classroom desk waiting for his return in the New Year.

But John Smith never went back to the school he loved and to the playground where he would squeal with delight as he ran with his chums.

By Christmas Eve 1999, his four-year existence had ended, an innocent life cut short.

He was let down by a social services system supposedly caring for him, let down by social workers who could have helped him, robbed of opportunities to see relatives and carers whom he loved, kept in his darkened bedroom for hours on end and ignored as he endured untold numbers of injuries.

No one can appreciate the mental torture, the tears and pain the little boy suffered in the six months he spent with the McWilliams. Yet, even in their care, he would manage smiles with his twinkling eyes and he would often play happily.

These were joyful interludes for a boy who, according to those who knew him, some only briefly, brought bundles of joy into their lives.

They described him as lovely, friendly, eager to please, delightfully-sociable, polite boy who adored adult and child companionship alike.

Born on May 19, 1995, John was loved by his natural parents Marion and John Smith, who live in Hove, but they could not keep him. His speech development was poor and his emotional needs were not being consistently met.

He was fed solids too early, was not thriving and his father had been accused and acquitted of abusing a child. Social services were worried and insisted the father move out. Mrs Smith became depressed and suicidal.

Following one attempt to take her life, her husband stayed the night to help her but social services found out and the boy was taken into care.

Mrs Smith, 42, will never forgive social services for taking John from her. She said: "He would be alive today and happy. I would have looked after him.

"He was a placid little boy, chirpy and cheerful. He loved sitting with a tube of sweets and drawing with pen and paper. He was considerate and put other children first, making sure they had sweets before he had his."

She remembers her last goodbye. "I told him when he was older to find mummy. He said he didn't know how but he would try. In the wrong way, he has come home to me now."

John was two-and-a-half when he moved in with foster parents Pauline and Rod Mears at their home in Telscombe Cliffs where he spent 17 months in a happy, caring environment.

He would rise early each morning and sing in the kitchen with 60-year-old Mrs Mears.

She said: "He was lively, happy and cheeky . . . his eyes would laugh at you."

He thrived at their home and the Mears would have applied to adopt John had they been younger. They were sad and upset when he went to the home of his prospective adopters.

John's life with the McWilliams began well and he settled in quickly. Mrs McWilliam was especially pleased, at last fulfilling her need to mother.

There were many happy times with the McWilliams and they loved him but they had not been properly prepared for the realities of child care, that boys will be boys, that children play up and are sometimes aggravating and difficult.

The McWilliams wanted to be the sole focus of his love and became jealous of anyone John showed affection for. The Mears were allowed only one visit and then vanished from his life, discouraged by reports that seeing them had upset him. It had not.

During the visit, he asked the Mears if he could go home with them.

John's social worker Dave Pamely, whom he loved, was discouraged from visiting on the same basis. During another visit, John climbed on his lap and sobbed his heart out.

John adored his classroom assistant Carol Antonini, a woman described as warm, motherly and kind. When John cried that he wanted her to be his mummy, contact with her was stopped.

He enjoyed visits from a community family worker but these were stopped after two sessions.

John worshipped his grandfather James Sweeney but a contact visit was postponed to a time, as it turned out, after the boy's death.

John shouted out at school and would often hug and kiss classmates as he tried to make friends and be loved. Teachers said he was very bright, cheerful and lovely but he was kept off school the last week of term and missed events he wanted to be part of.

He often arrived at school with bruises but the McWilliams explained John was self harming.

John himself would tell people he had hurt himself and, when asked why, he would say simply: "I don't know."

The McWilliams denied they threatened the boy not to tell.

John was a bad eater and would often spit out food and sometimes vomit. Police speculate this could have been the trigger for his injuries.

One officer said: "McWilliam was under pressure with his university course and his wife was doing contract electrical assembly work at home.

"It was a tall order for any parent, let alone inexperienced ones. It got too much for the McWilliams and things flared up at meal times. They had expected a model child but there is no such thing."

On one occasion, after John was sick at breakfast and lunch, he was sent to bed in his darkened room at 12.30pm for six hours. He was allowed no food and, apart from a short break, was not allowed from his room until the following morning.

John suffered injuries from August to December and had begun stuttering, probably through the trauma of his ordeal.

His last few days at 72 Gardner Road, Fishersgate, Southwick, were the things of horror films.

A child's screams of "No, daddy" were followed by dull thuds interspersed with crying.

College teacher Janet King, who lived next door, was having a morning bath.

She said: "Suddenly I heard a child crying rather hysterically. Then I heard what I assumed was a boy screaming 'no daddy'. Then I heard three or four dull thuds with crying in between. I was horrified. I dropped my book. I was quite worried.

"The little child sounded so frightened."

On the day before John's death, the McWilliams' other next-door neighbours, Sharon and Paul Howard, heard noises. Mrs Howard said she was woken early on December 23 by banging. It appeared to be from the McWilliams' front bedroom.

She said: "It was like a ball, like a basketball. It lasted for about a minute then it stopped. It went on for 30 minutes with breaks in between."

John was brain-stem dead a few hours later and he died the following morning.

Despite the violent and frightening nature of his home life, John had managed a cheerful exterior to those who saw him in his last few days. Many attended court and some periodically left the public gallery to weep privately outside.

John's placement with the McWilliams had proven a disaster. It had taken from them a loving, caring little boy who never stood a chance.