Thousands of child refugees are waiting in Greece near to the border with Macedonia.
Lots of them have fled their home countries, such as Syria and Iraq, because of wars there.
Many of them are hoping to reach other European countries like Germany.
However, the authorities in control of the border in Greece are only allowing a small number of people to cross over each day.
This means lots of people are left stranded there with very little belongings and food.
BBC reporter Gavin Lee is at the border and sent us this report.