This normal, a normal part of grieving their losses, but it should not be ignored. Be prepared to be more supportive, to be with them more and to listen. Children usually adjust better than parents, but they too may exhibit problems in school. With the permission of the parents, you may want to check with teachers to ensure everything is going well. Adolescents may have special difficulties because the cultural expectations of their parents are different from those of their friends parents.
Refugees are first and foremost people.
They are not all the same. They will adjust in their own individual ways to life in Canada. However, most will undergo some ups and downs, particularly in the first few months of their lives in Canada. Many will long for home and will cling to the past. The may be very angry.