She was heavily pregnant when she went to jail and gave birth to her son while serving her sentence.
The newborn, whom she held only briefly, was then cared for by her relatives.
But weeks before her release, she was told that her baby, then four months old, had died.
A coroner's inquiry into his death found that his 21-month-old cousin had pushed the stroller he was in on March 2 last year.
The stroller, which had not been secured properly, folded and collapsed to the floor, causing him to suffer fatal head injuries. He died the next morning.
The victim, his mother and his carers cannot be named to protect the identity of his cousin.
His mother, whom we shall call Madam Farah, 33, was jailed for a year in 2013 for loan-sharking offences.
Her son was being cared for by her half-sister and the sister's fiance. The half-sister is the mother of the cousin.
Speaking to The New Paper in her two-room rental flat on Tuesday, Madam Farah recalled her complicated relationships and the day she got the heartrending news about her young son.
She said she was sent to jail in September 2013 for working for a loan shark.
"I know I've been to jail. But I'm also a mother and I love all my kids very much," said Madam Farah, who has five other children - two boys and three girls.
Three of them, a 17-year-old girl and her brother and sister, are with their father, Madam Farah's first husband.
Her second marriage, which also ended in divorce, produced another boy and a girl.
They are now living with her and her stepfather, a security officer who makes about $2,000 a month and supports the family.
The son who died was from her third marriage, which she said was on the rocks, with a divorce imminent.
Madam Farah is now six months' pregnant with her seventh child, whose father is another man.
Recalling her time in prison after she gave birth, she said she was counting down the days when she could finally be reunited with her baby.
But tragedy struck about two months before her release from Changi Women's Prison.
She will never forget the day when she received the tragic news, she said.
It started with her inmate number being called up.