From the Guardian, writer Karen McVeigh details the appeal for Sri Lanka.
More than 1 million people in the country are affected, with over half estimated to be facing food shortages and the threat of waterborne disease.
It is an enormous setback for an area that was only just beginning to recover from the decades-long war and the 2004 tsunami which killed 400,000 people and left 2.5 million homeless.
"The average ten-year-old in eastern Sri Lanka has lived through conflict, the tsunami and now risks facing a food crisis in the coming weeks caused by these floods," Gareth Owen, Save the Children's emergencies director, said.
"It is absolutely essential that the world does not wait until these children are starving to act.
"Many families in affected areas are facing a nightmare scenario in which both their food source and their livelihoods have been washed away by the rains. They need help to survive until the next harvest. It may not have been possible to prevent the floods, but we can avoid a food crisis if help is given to families now."
An estimated quarter of a million acres of agricultural land and more than 240,000 livestock are thought to have been lost when the east of the island was hit.