Now, this same province is the epicentre of a new Ebola outbreak that threatens to further increase the chaos.
In war-torn North Kivu, boys as young as 14 describe being forced to fight on the battlefield under a spell of "Juju", or black magic, so they wouldn't be afraid of bullets. Girls describe being abducted by armed groups and forced into marriage with their captors.
A Save the Children analysis of more than 10 years of United Nations data showed a dramatic increase in atrocities against children in the DRC. Last year saw the highest level of verified child casualties on record, and the highest level of recruitment of child soldiers for nearly a decade.
Anita was forced to marry a fighter at the age of 15, a year later she managed to escape
"It's children like these who are paying the price for this brutal, forgotten conflict. They have been robbed of their childhoods. And without urgent medical and psychological help, they could lose the chance of building a future," said Save the Children's Country Director in DR Congo, Heather Kerr.
"We're on the ground giving as many children as we can the tools they need to rebuild their lives. But there are thousands more who are on their own. With the right support, we could reach them.
"These children have seen things that no child should ever have to see. We can't change their past, but with the right support we can help rebuild their lives"