The jury has retired in a case where a mother is accused of killing her son aged nine by poisoning him with salt.
Petrina Stocker denies killing her nine-year-old son, David
Petrina Stocker, 42, of Romford, Essex, denies manslaughter at the Old Bailey.
The boy called David fell ill and died in August 2001 from an overdose of salt which the prosecution alleged was put into his drip feed.
Her defence says there is no evidence against Mrs Stocker and no proof of who added salt to the feed. Mrs Stocker is also alleged to have misled doctors.
Jurors were told David died in Great Ormond Street Hospital in August 2001.
The prosecution alleges she poured salt into a milk feed at the children's hospital after spending months trying to trick doctors about his symptoms.
Mrs Stocker denies doing anything to harm her son. She says she does not know how the salt got into the feed.
A post-mortem examination found he died of sodium chloride poisoning, despite being on the salt-free milk feed.
At the time of his death, David also had wasted muscles consistent with chronic anorexia or chronic natural disorders.