A mother who won a change in the law after her son was tortured to death has said her son “died in vain” after tougher sentencing rules were not used against the killers of Baby P.

Marion Smith's son John Antony(COR – no h) was beaten to death by his foster parents on Christmas Eve 1999.

With the help of a campaign by The Argus, Mrs Smith got the law changed to hold any adult household member culpable for the murder of a child or vulnerable family member unless they took steps to stop it.

Yet those responsible for the death of Baby Peter in Haringey - named last week as the child’s mother Tracey Connelly, her paedophile boyfriend Steven Barker and his thuggish brother Jason Owen - escaped with relatively short jail terms.

Connelly was told she would serve a minimum of five years while Barker was locked up for 12 years and Owen for three years.

Mrs Smith is demanding to know why the tougher sentencing she had campaigned for had not been used.

She said: “I am so angry.

“Have they learned nothing from my John Antony’s death?

“We fought to change the law that let my boy’s killers walk out of jail after less than five years. When I heard that Baby P’s evil mother could serve the same I wept. Did my boy die in vain?”

“I haven’t seen our law used once.

“It feels like John Antony’s death was for nothing.”

Simon and Michelle McWilliam, of Southwick, were jailed for eight years each for child cruelty after the death of John Antony. A legal loophole allowed them to escape a murder charge because police could not prove which of them had struck the killer blow.

Simon McWilliam, now 49, was out in five years while, Michelle McWilliam, 43, served just four years.

The familial homicide offence, known as John's Law, holds a 14 year maximum sentence.

When John Antony died of a brain injury aged just four, doctors were shocked to discover 54 injuries including three adult bite marks on his tiny body - all of which had been missed in numerous visits by welfare workers.

Mrs Smith said: “Just like little Baby P, my beautiful boy was visited again and again by social workers while he was being abused.

“They saw his bruises and yet they did nothing.

“I want people to remember all the Baby Ps, all the forgotten children who have been brutalised and murdered, and all the promises that have been made in the aftermath and just as quickly forgotten.”

Cursory checks on the McWilliams would have revealed they were unsuitable parents.

Accountancy student Simon was described in court as a cruel “Jekyll and Hyde” tyrant to his two ex-wives and Michelle's criminal record showed she had a history of petty offending.

But social workers lauded the couple as the “the brightest and best applicants” to adopt John Antony.

They visited the McWilliam's home 20 times in the six months before John Antony died. Simon McWilliam fobbed them off with the excuse that John Antony’s many unexplained bruises were self inflicted.

Mrs Smith said: “My little boy is in the ground when he should be growing into a young man with all of his life ahead of him.

“It happens again and again, the same story, the same failures, the same guilt from the people who suspected but did nothing.