A 75-year-old retiree slapped her daughter's maid, knocked her head against a wall and even poured bleach on her hands - all because she ate some salmon which had not been meant for her.

The ordeal prompted Filipina Jonna Memeje Muegue to escape their Maplewoods condominium by jumping from a sixth-floor bedroom window, breaking both her legs when she landed on a fifth-floor rooftop.

Retired radiograph and medicine technician Lum Wai Lui was sentenced to 21 months' probation for the 2012 attack yesterday.

The court had earlier heard how her family's 27-year-old helper lost 10kg during her 10-month stint at the Bukit Timah Road household.

Lum was found guilty in May last year, after a six-day trial.

But an Institute of Mental Health psychiatrist found that she was suffering from depression and schizophrenia with "persecutory and bizarre delusions", which "contributed significantly" to the offences.

Among other things, she believed that the domestic helper was having affairs with her sons-in-law.

As part of her probation sentence, meted out by District Judge Lee Poh Choo, Lum will have to continue with her psychiatric and psychological treatment, and also cooperate with her probation officer, who must be consulted if the family wants to hire another domestic helper.

Her daughter, Ms Kathleen Chua Siew Wei, 42, posted a $15,000 bond to ensure Lum's good behaviour.

Ms Chua, who still lives with her mother, was acquitted last year of slapping Ms Muegue some time in May 2012. The prosecution's appeal against her acquittal is expected to be heard in the High Court next month.

Meanwhile, Ms Chua's sister, Chua Siew Peng, 44, who is Ms Muegue's former employer, has been convicted of wrongfully confining Ms Muegue at the condominium on Oct 30, 2012, and also of slapping her the night before.

The elder daughter no longer lives with her mother. She will be sentenced at a later date.

Deputy Public Prosecutor Yang Ziliang, who had sought 24 months' probation for Lum, also asked the judge to impose a compensation order.

But defence lawyer Quek Mong Hua objected to this, noting that Ms Muegue had started a civil suit against Lum last October for loss of income and general damages.

Lum and her family had also paid for Ms Muegue's hospital and nursing home bills, as well as follow-up medical expenses, which amounted to more than $24,000.

The judge found that the civil suit would be a more appropriate forum to decide on compensation.

Ms Muegue now works for another family.