When Madam Yap saw her daughter's swollen left ear, she was horrified.
Her daughter is just over 2½ years old.
Madam Yap, 41, like the other parents we interviewed, asked that we not use her full name.
She said she noticed that her daughter's ears were unusually red when she picked her up from her nursery, Chiltern House at Orchard Road, at around 5.30pm on May 22.
Madam Yap, the managing director of an European multinational company, said her daughter, Julia (not her real name), complained of pain in her ears and was crying on the way home.
When Madam Yap asked her what had happened, the girl initially refused to say anything.
"She kept making the action of zipping her mouth and said 'cannot say, cannot say'."
After Madam Yap kept assuring Julia that she would not tell anybody, the little girl finally revealed that her nursery teacher had brought her and another toddler from the same class to the diaper changing room.
When Madam Yap asked Julia to show what the nursery teacher did to her in the diaper changing room, Julia twisted her ears and roughed her face with both hands.
Madam Yap believed this meant that Julia's ears were pulled and she was abused by the teacher in the room.
"I believe the teacher is also the one who told her not to tell anyone. That's why she only cried and said 'cannot say' at first," said Madam Yap.
She then called Madam Tan, the mother of the toddler who was in the diaper changing room during the alleged abuse.
Madam Tan, 34, a property agent, immediately examined her daughter Anna (not her real name) and noticed that Anna had two scratches on her right cheek and red ears too.
"I didn't notice this right away because the injuries were not that obvious," said Madam Tan.
"And Anna, unlike Julia, is quieter. So she didn't tell me anything at first.
"Anna is not the kind who would bring up to me what happens in school unless I ask her directly."
When Madam Tan asked Anna if her red ears were because of the nursery teacher, Anna said yes.
"Anna also told my maid who was bathing her that evening, 'Come with me to school on Monday to punish the nursery teacher. She was naughty'.
"I couldn't understand why she would say that to my maid at first.
"But when Julia's mother called me about the possibility of our daughters being abused, I realised why," Madam Tan said.
The New Paper understands that the nursery teacher who allegedly abused the toddlers is new.
She was transferred to the Orchard branch of Chiltern House only about two weeks ago.
Madam Yap told TNP that Julia seemed slightly traumatised and had nightmares after the incident.
She believes the incident in the diaper changing room was not the first case of physical abuse by the new teacher.
She said that when Julia told her how her ears were pulled by the teacher, she mentioned an incident earlier in the week when the teacher smacked another classmate on the head.
"Julia said she saw the teacher hitting the boy's head. He then cried."
She informed the boy's mother, Madam Lee, who confirmed this after asking her son.
Madam Yap reported the abuse cases to the police at around 11.30pm the same day, before bringing Julia to KK Women's and Children's Hospital for a check-up.
A police spokesman told TNP last Thursday that investigations were ongoing.
The principal of Chiltern House, Ms Iris Lee, met the affected toddlers' parents last Wednesday afternoon to discuss the incident.
Ms Lee said the teacher has been suspended and the school management will decide what to do after police investigations are completed.
"It is most unfortunate that such an incident happened, but the school will do its best to ensure that lessons are not disrupted for this class.
"The interests of the children, parents and even the teacher herself is our top priority," said Ms Lee.
During the meeting, parents raised concerns over the lack of closed circuit television (CCTV) in the nursery centre and questioned the centre's recruitment process.