After bombs started falling in her hometown of Kharkiv, Annamaria Maslovska left her friends, her toys, and her life in Ukraine and set off on a days-long journey with her mother toward safety in the West. After finally crossing the Hungarian border by train along with hundreds of other Ukrainian refugees, the 10-year-old Maslovska said she had begun to worry about her friends in Kharkiv after the messages she sent to them on Viber went unanswered. “I really miss them because I can't contact them, they just read my messages and that's all. I really worry, because I don't know where they are,” she said in clear English from inside the train station at the border town of Zahony. Annamaria, who was raised alone by her mother, is one of more than 1 million children who have fled Ukraine in the less than two weeks since Russia first invaded the country, something UNICEF spokesperson James Elder called “a dark historical first.” That means that children represent around half of the more than 2 million people that have fled the war, an exodus that the UN refugee agency has called the fastest-growing refugee crisis in Europe since World War II.