Authorities in Greece say three children have died after the dinghy taking them from Turkey to the tiny Greek island of Agathonisi overturned in the Aegean.
The Coast guard said 20 people were rescued and the children's bodies were recovered.
The Malta-based relief agency Migrant Offshore Aid Station was involved in the rescue effort.
Greece is the European Union's busiest entry point for migrants and refugees entering the bloc, with a dramatic spike in the number of people fleeing the civil war in Syria last year.
Refugee crisis has hurt EU's reputation
European Commission President Jean-Claude Juncker says the EU's reputation is being damaged worldwide for the failure of member countries to manage the refugee crisis.
Juncker on Friday called on nations to host more refugees arriving on Europe's shores, after more than one million migrants entered in 2015.
He said it is unacceptable "that certain member states say they are not going to accept refugees in their countries. That is not possible."
Juncker said Europe was known as a wealthy, admirable continent but that "now we do appear as being the weakest part, and the poorest part of the world."
He said he was embarrassed explaining Europe's migrant problems to leaders of countries like Jordan or Lebanon, which are hosting more than two million refugees.