The 17-month-old boy who was found dead in the waters off Bedok Jetty on Monday was cremated at Mandai Crematorium on Wednesday.
This comes a day after the infant's mother, Lim Ann Nee, 44, was charged with his murder.
When The New Paper visited her relative's home on Wednesday afternoon, a family member said Lim and her husband, a Frenchman, had planned a trip to France and were supposed to leave on Dec 15.
"They had even bought the plane tickets. I don't understand how something like this could have happened," he said in Mandarin.
On Monday, Lim and her son had reportedly gone for a walk in the rain.
When they did not return, the baby's grandfather, Mr Lim Joo Hing, put up an alert on Facebook at about 3pm, asking for help to locate the infant.
Lim was found later at about 6pm, off the waters of East Coast Park by the Police Coast Guard.
She was taken - while still conscious - to the Singapore General Hospital (SGH) for treatment.
Her son, Emilien Lacroix, was found dead about three hours later in the waters off Bedok Jetty.
His body had been spotted by a passenger in a passing boat.
Shin Min Daily News reported previously that the boy was dressed in a orange shirt and red shorts before the incident, but he was naked when found.
Lim was remanded at Changi Medical Centre for psychiatric evaluation after being discharged from SGH on Tuesday.
She is expected to appear in court again in about two weeks.
Lim faces the death penalty if convicted.
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