It was the children who bore the brunt of the disaster in south-east Asia.
By Christian Fraser
BBC News, Banda Aceh
Child protection is one of a top priority for Unicef in Banda Aceh
Thousands were killed or injured, thousands more were separated from their parents.
In Indonesia, the work is now beginning to try to identify those who have been orphaned - it is a difficult task made more complicated by the loss of family records and the burial of the dead without any identification.
In recent days, rumours of child-trafficking have forced the government to freeze any movement of children outside the affected areas.
But already there is informal adoption taking place by family and neighbours which further complicates an already difficult situation.
This is Iwa's story and, for a seven-year-old boy, it is a difficult story to tell.
He told me he was doing his homework when the earthquake struck.
He left the house with his father and together they ran but when they looked back, he says, his grandma was still in the bedroom, being shaken about.
Iwa now lives in a camp in the grounds of a television station. It is home to several thousand survivors of the tsunami but Iwa is one of the luckier ones.
He still has his parents. There are many others who do not and who may well be orphans.
And the job for the United Nation's children's agency (Unicef) now is to try and reunite families.
"We have the database that actually comprises information about the kids with our registration number and names, ages, schools, name of fathers, name of mothers," says Unicef's project officer in Banda Aceh, Danny Poruba.
Mr Poruba says Unicef staff check information when someone comes to the tent claiming to be searching for his or hers children.
"But we are mostly [here] to protect the kids from anyone who can come in and take the kids away.
"Even though he has all of the information, all of the documents we require, we still need to go through the government to have approval from the government."
We left Iwa's camp to visit the children of Fakina Hospital but when we arrived, one of the Indonesian doctors told us they had already gone.
Many children are still being treated in Banda Aceh's hospitals
"This is the children's ward, but now it is empty because most of the people have left," a male doctor said.
"We agree that if they are still here, another person will come... but... they don't know where to go, because there is no place, his house, there is no house, there is no family."
There may be very good reasons why the children's ward is empty.
Some are known to have been evacuated, some already collected by surviving relatives or neighbours.
The trouble is, no-one really knows because there is no registration of child patients.
On the way out, I met Sepal Bari. His wife is still missing, but his two-month-old daughter, sitting on his knee, miraculously survived.
"Some people tried to adopt my daughter several times, but I rejected," says Mr Bari through an interpreter.
In response to my question whether he was suspicious who these people were, Mr Bari says: "You can see beside you there are two people here who want to adopt his daughter right now.
"I already knew about the child-trafficking so that is why I don't want to give up my daughter to somebody else."
In fact, he had been approached seven times in this hospital.
It is a story that raises serious concerns for child protection officers and Unicef's Brigitta Len Hendriksson says there are other cases:
Bodies are still being found - almost two weeks after the tragedy
"One is a couple that has brought a child out of Aceh to Medan. When they arrived there the child was sick so they went to a hospital for medical attention.
"There, NGOs intervened as part of their registration follow up with victims and they grew suspicious when the couple were inconsistent in their stories, basically.
"The other case is a 41-year-old man who came into a hospital in Medan and smuggled a boy who is one of the victims from Aceh, or tried to smuggle him out of the hospital.
"He was handed over to police for questioning and his story is that he is the neighbour of the boy. I don't know the outcome of that."
I asked her if she was worried that the children's ward at the Fakina Hospital was empty.
"We were concerned about the fact that children are being evacuated out for medical purposes without proper registration so it is not clear where these children are ending up and who they are," Ms Hendriksson answers.
There is only 40% registration of children in Indonesia and - with family records here being washed away - it will not be an easy task to keep track of children.
And in a region that has a long, depressing history of child-trafficking, it is a matter of urgency that the most vulnerable are identified and protected as quickly as possible.