Imagine waking up in the morning without knowing where you will lay your head that night. That's now the fate of millions of children around the world whose families have been swept from their homes by civil war and violence. Of the world's 19.5 million refugees, more than half are kids , according to the United Nations High Commissioner for Refugees.Swedish photographer Magnus Wennman has been traveling through Europe and the Middle East documenting what has become the worst refugee crisis since World War II . Sadly, for those who have already fled to safety, conditions could soon get even worse. Events as disparate as the recent attacks on Paris , which have caused European nations and some U.S. states to reconsider their willingness to take in refugees, and the arrival of winter, with its freezing temperatures, could have disastrous consequences for people now forced to take shelter, sometimes on any patch of ground they can find. Aid groups say there is real concern that many people could freeze to death if nothing is done.Wennman told Refinery29 that capturing photographs of Syrian children in their makeshift beds — in fields, hospitals, and city squares — has been a particularly eye-opening experience for him."I felt this project was more personal for me than others, perhaps because I have a 5-year-old son and I know how important it is for him to feel safe every night when I put him to bed," Wennman said. "The children are the most innocent victims of this conflict. They did not choose to leave their homes. Many of the children have told me that they especially remember the sounds of the bombings."Above all, they face a world of uncertainty. "No one knows if or when the conflict will end and what country Syria will be. Some of these children will start their lives in new countries and can, and will, probably have a great future. Others will be stuck in refugee camps in the neighboring countries," says Wennman. "Many will probably never return back to Syria."Click through for the powerful photos and stories of these refugee children. All photo captions were written by Magnus Wennman.Refinery29 has also partnered with USA for UNHCR to support refugees around the world. You can make a difference with your donation here: UNrefugees.org/Refinery29 Photo caption: Iman, 2, lies in a hospital bed in Azraq, Jordan. Iman has pneumonia and a chest infection. This is her third day in this hospital. "She sleeps most of the time now. Normally, she's a happy little girl, but now she's tired. She runs everywhere when she's well. She loves playing in the sand," says her mother, Olah, 19.Refinery29 is committed to telling the human story behind the headlines of the Syrian refugee crisis. To read the story of three Syrian women forced to flee violence and civil war, and how they have rebuilt their lives in Turkey, read "Daughters of Paradise" here . For full coverage of the Syrian refugee crisis, read more here