Some of Kieran Peers' remains were retained

Alder Hey was at the centre of a major scandal in 1999 after it emerged that pathologist Dick van Velzen had hoarded thousands of children's organs at the hospital without consent of parents.

Mr Cohen said: "We are seeking a change in the law.

"It will be for the benefit of the medical profession as well as the families.

"It would make communication with families mandatory, and would restore faith in the pathological process."

In a statement, the hospital said: "A post-mortem involves creating blocks (parts of organs) and slides of tissues for microscopic examination to help determining the cause of death. This was done by order of the coroner.

"The creation of blocks and slides often requires that parts of organs - sometimes whole organs - are removed and kept until after the funeral would normally take place."

Mike Peers, the boy's father, said: "I said I want everything putting back once he's had his post-mortem, anything that doesn't need to be kept, as in, like, small tissue samples for histology - they explained all that to me."

Mr Cohen said: "They (the family) gave explicit consent for samples to be taken on condition that the brain and other tissues and organs would be reunited with the body.And that hasn't occurred here."