A 35-year-old woman was arrested last week after parents complained that their babies became listless after she babysat them.
Mr Tan, who asked that his family members' names not be revealed, said that his 11-month-old daughter is still in hospital after spending eight hours at the nanny's home in Hougang on Christmas night.
They did not normally engage a nanny, but had an emergency to attend to that night, he said.
They found the nanny, who claimed to be a former nurse, through a Facebook group for mothers. She charged them $30.
His wife said that when they dropped their daughter off at the flat, the nanny looked “decent” and assured them that she would take good care of the toddler.
But when they went to pick their daughter up the next morning at 6am, the usually active child was drowsy and her eyes were half-closed, Mr Tan said.
“She looked drugged, was cranky and couldn’t sit straight.”
Even a nap, his daughter still appeared drowsy and could not control her limbs.
Mr Tan said that his daughter seemed better but was "still not coping well" and will be hospitalised until next week.
At least two police reports were made against the nanny. During the arrest, police took away medicines from the nanny's home including cough mixture.
Police said investigations are ongoing.
By Chew Hui Min, The Straits Times, December 2016