What is the most important message or theme in the book?

Immigration is the main theme of the book. In the entire memoir The Happiest Refugee, Anh Do narrates his life history reflecting on how his family run-away from Vietnam when the war came to an end. The immigration to Australia comprised of the entire extended family, Anh's father, mother, siblings, aunts, and uncles. Life in Vietnam is very difficult and there is no peace. Their only hope is to get an escape route and travel to Australia using a boat to search for a better life. During this time, Anh and his brother are still young boys.

The family is lucky in its journey because it arrives safely in Australia despite meeting many obstacles on the sea. Anh's sister is born in Australia. Anh provides a detailed explanation of what the family goes through as they arrive in Australia where they are referred to as refugees. In Australia, the extended family members move to various locations to start the new life. Anh goes to the law school where he meets Suzie and they fall in love. They later get married and blessed with three sons. Therefore, the entire memoir is an account of how Anh and his family migrated from Vietnam to Australia where they settle as refugees.