The oldest sibling is thirteen years old. The others are nine, four and the smallest only 11 months old.
In the crash a month ago, the children's mother, the pilot and another adult were killed. Early in the search, they found a baby bottle and diaper that are believed to have belonged to the children.
Now new traces of the children have appeared during the search in the jungle: an improvised shelter, half-eaten fruits and a new footprint of a child.
"This is a new trail that was found about two kilometers from the previous one and it indicates that the children are still alive," Fausto Avellaneda, a colonel in the Colombian army, said on Tuesday.
200 participate in the search
The army plays an audio message from the children's grandmother on the megaphone and lets it echo across the jungle. Food has also been placed and large numbers of leaflets have been thrown out of helicopters with instructions on what to do.
About 200 people are taking part in the search, both soldiers and volunteers from the indigenous people of the jungle.
"You can't take it in, but God is powerful, so I know that my children are alive and that we will find them," says Manuel Ranoque, the children's father.