As a mother, she was supposed to protect her young daughter from sexual predators. However, the cook turned a blind eye to her live-in boyfriend's sexual abuse of the child, which included rape.
Even though the girl told her mother that the man had done "sexual things" to her, the woman did not stop him from showering with the girl on multiple occasions.
The former taxi driver - who was married at the time - sexually abused the child from 2010 to 2016 and his offences came to light only when the girl told his wife about her ordeal.
The mother, a 40-year-old divorcee, was sentenced to the maximum six months' jail yesterday for intentionally failing to alert the police despite having reason to believe that an offence had been committed. She cannot be named due to a gag order to protect her daughter's identity.
The 47-year-old man was sentenced in February last year to 34 years' jail with the maximum 24 strokes of the cane, after pleading guilty to four counts of rape.
He was referred to as "A" in the court documents.
Deputy Public Prosecutor Chee Ee Ling said that the cook entered into an "illicit" relationship with the married man in 2006.
He started molesting the girl when she was placed in his care during the 2010 school holidays. She was only about eight years old at the time.
The girl later told her mother about the acts but the man denied committing the offences when the woman confronted him.
DPP Chee said: "Eventually, the victim stopped telling the accused of these sexual assaults, when she realised that it did nothing to stop A and only created a hostile atmosphere - where the accused would confront A, who would deny and they would both quarrel... The victim, resigned to her fate, simply allowed A to molest her."
In 2014, the girl and her mother moved into the man's Clementi flat.
DPP Chee told District Judge May Mesenas: "Slowly, A grew more brazen and even asked the victim, then 11 years old, to accompany him in the shower for sexual intercourse during the daytime in the accused's presence. This was bizarre, especially since A did not shower with his own biological son who was two years younger than the victim."
The man's wife filed for a divorce in 2016 and moved out of the flat with the son.
The man then moved into his girlfriend's flat, where he continued to sexually abuse the girl.
In June that year, he continued to shower with the girl, then 13 years old, and had sexual intercourse with her in the bathroom while the mother was in the flat.
Unable to endure any more abuse, the girl finally told the man's wife about her ordeal and she referred the teenager to a social worker. The police were notified on June 29 that year.
The mother, who was unrepresented, pleaded for a light sentence yesterday. The girl now lives with her maternal grandparents.