Fifteen-year-old Fazly would spew vulgarities. Aqib, 13, would scream for no reason. Eli, 10, would wander around and run wild in a mall or supermarket.
All three have learning or behavioural problems and need special care.
But to Madam Norli Fargi, 51, they are perfect just the way they are.
"They are good children but there are times I wonder where they come from and feel that they need to change," she said, referring to her foster children's family background.
"If you give them love, if you care for them, if you talk to them nicely, surely they will change."
Madam Norli fosters Fazly, Aqib, Eli and a girl, Siti, 16. Their names have been changed and we are not naming their specific conditions to protect their identities.
Children who are placed on the fostering scheme lack alternative kinship care arrangements due to various reasons. Their parents could have a physical or mental illness and are unable to care for them, or they could be victims of neglect or abuse.
Contrary to popular belief, the needs of children with learning or behavioural challenges do not differ much from other children their age.
Th!nk Psychological Services' clinical psychologist Matilda Chew said: "While these children may indeed require more care, particularly if they are not catching up with their peers in terms of development and learning, children with special needs flourish in a consistently nurturing and structured environment - just like typically developing children."
Madam Norli agreed: "I don't see them as any different from other kids. I treat them all the same way. We just have to know how to tackle them."
She has to slowly repeat herself several times before her three special needs foster children can understand her.
Fazly, who goes to a mainstream school, used to stammer and had difficulty understanding his teachers. For a period of time, he even hid his homework from Madam Norli because he did not know how to complete it.
An exasperated Madam Norli found out only when she spoke to his teachers. From then on, she kept in close contact with his teachers, who would visit her five-room flat in the north-western part of Singapore whenever there is homework for Fazly.
He now goes for reading and speech therapy classes and is "almost like a normal kid", Madam Norli said with pride.
Eli, who has delayed learning abilities, tends to wander around whenever she is in a mall or a supermarket.
"I make her push a trolley so that she can't run," said Madam Norli.
Aqib, who joined his siblings Fazly and Siti at Madam Norli's home two years ago, knew nothing about social norms. He would speak loudly, scream or throw tantrums.
"When he first arrived, he would get frustrated very quickly. Then he would bang on something with his fists," said Madam Norli.
Aqib also seemed unable to do things children his age could, like taking the MRT.
"He would ask questions like 'Why is the MRT crowded?' or 'Why is this round?'" said Madam Norli.
"He doesn't know a lot of things that may seem normal to us. But it's good that he likes to ask questions."
She talks to Aqib about cars, which he is fond of, to motivate him to learn and ask more questions.
Madam Norli's two biological daughters, Nur Hidayah, 12, and Nur Khairunnisa, 19, get along well with their foster siblings.
The family of eight depend on what Madam Norli's husband, Jafri Mohd Yusof, 51, earns as a warehouse assistant and a monthly fostering allowance provided by the Ministry of Social and Family Development (MSF).
The allowance pays for the foster children's needs, like food, clothing, transport and school fees.
For every foster child, a foster parent gets $936 every month, and $1,114 if the child has special needs.
Foster families also enjoy childcare subsidies and exemption from medical fees.
Since she started fostering in 2003, Madam Norli has parted with four foster children who stayed with her for weeks or months before they returned to their families.
"Of course I felt sad," she said.
"But my husband gives me emotional support. He always says that when one goes, there are more out there who need us."
The heartwarming moments, to Madam Norli, are the most rewarding part of fostering.
"Sometimes, when I feel sick, they ask me, 'Mummy, how are you today?'
"You see, it's very touching. They even plan surprises with my husband for my birthday.
"As long as I am healthy and have the support of my family and MSF, I'll do it."
Foster son has special needs but he's family
She almost grew to accept the silence between her and her foster son Alan (not his real name).
Madam Susan Wong didn't know then why he refused to speak. She declined to disclose Alan's age.
"We thought he did not understand what we were saying. But one day, when I was taking him to school, he called out for me," said Madam Wong, 54.
To this day, the foster mother cherishes that moment.
"I thought he didn't know much about what was going on with our family but he actually did," she said.
"It motivated me to do more to help him develop his speech skills so that he could communicate better with us."
Madam Wong, who has a 19-year-old biological son, started fostering in 2010.
She discovered her passion in caring for children after babysitting her French-Chinese neighbours' daughter.
Shortly after her application to become a foster parent was approved, Madam Wong welcomed Alan, then a baby, into her family.
"There were no objections," said Madam Wong.
"My family loves children, especially my late father.
"My husband voiced his concerns over whether I could cope with the additional responsibilities, but he was still very supportive of my decision."
She discovered Alan's problem when he was a toddler. During a medical check-up over his inability to speak, he was also diagnosed as having special needs.
Madam Wong said the boy would throw tantrums and be unreasonable.
"He was unable to let us know exactly what he wanted. For a period of time, he would just remain completely silent and refused to speak," she said.
"Despite his condition, we have since formed a close bond. He has become part of our happy, cosy family."
Now, Alan goes for speech and occupational therapy, which has helped to improve his speech and behaviour greatly.
"Seeing his growth and development is the greatest motivation for me to continue my journey as a foster parent," said Madam Wong.
"As long as I can, I will continue to care for him and look forward to achieving more developmental milestones with him."
More foster parents needed
Some foster parents may think that children with special needs are more difficult to handle.
These children have problems in their development, or have a learning or behavioural difficulty or both.
But that may not be the case, said Ms Norkhairaha Mohd Taha, a foster care officer with the Ministry of Social and Family Development (MSF).
Ms Norkhairaha, 33, said: "Families tend to prefer to foster younger children as they are perceived to be easier to care for.
"So there is a need for more foster parents to care for older children, specifically seven years old and above, and those with special needs."
Children may be placed under the fostering scheme because their parents have died or are in jail, their parents or families are unable to care for them, or they are victims of neglect, abandonment or abuse.
Most of the time, fostering is only a temporary arrangement to meet the emergency care needs of a child.
The ultimate goal is to reintegrate these children with their natural families.
"These children yearn for the same things as their peers: a nurturing and safe home environment that will provide them with the love and care that they need," said Ms Norkhairaha.
Th!nk Psychological Services' clinical psychologist Matilda Chew agreed: "It is important to remember that most children requiring foster care placement have experienced life circumstances that other children from typical families do not, such as a dysfunctional family background or abuse .
"This consequently places them at risk for neglect, malnutrition, modelling inappropriate behaviours and having attachment difficulties.
"In this respect, regardless of whether or not a child has special needs, he or she would require similar childhood needs to be met."
These include good nutrition, learning appropriate behaviour, receiving and giving love in age-appropriate ways, self-care and self-protection, as well as "the understanding that what happened to them is not their fault".
There were 355 foster parents as of last December, but MSF hopes to grow the pool to 500 in the next five years.
Foster care officers mentor and coach foster parents on trauma-informed care and help them understand the reasons behind the children's behavioural issues.
To find out more about fostering, call 6354-8799 or go to the MSF website at www.msf.gov.sg/fostering
This article was first published on February 10, 2016.
Get The New Paper for more stories.