Louise Sullivan, 27, pleaded guilty two weeks ago to the involuntary manslaughter of six-month-old Caroline Jongen, who died of brain damage last year.

Crime Correspondent Stephen Cape: "The judge was told that Louise Sullivan couldn't cope in prison"

Mr Justice Mitchell will pass sentence after considering new reports presented to the Old Bailey on Monday.

Sullivan's lawyers have argued she should be allowed to return to Australia for psychiatric treatment.

The court was told that Sullivan has an IQ of 81 - well below the average of 100 - and should not have been allowed to look after Caroline.

Psychologist Sarah Henley said: "Miss Sullivan functions on a very concrete, rigid way.

"It is particularly related to judgement and particularly to inability to be flexible."

Sullivan was alone with the baby at the Jongens' home

Sullivan's counsel, Nadine Radford, QC, said her client behaved inappropriately when she thought the baby was having a convulsion, but that it was not intentional.

Rather, she said, it was a result of Sullivan not having the ability to reason clearly in such a situation.

"This is not a case of someone losing their temper or being angry or anything else," she said. "It is someone concerned to do the best they can."

Three of Sullivan's former employers - called by the defence - praised her abilities as a nanny.

Earlier the infant's mother, Muriel Jongen, was helped screaming from the court after listening to nearly an hour of psychiatric and psychological evaluation of her former nanny.

Consultant psychiatrist Dr Henry Kennedy said he believed that Sullivan had started to express grief and remorse.

Dr Kennedy said: "Not a day goes by without her remembering baby Caroline. She thinks what she might be doing now if still alive.