Squirrel is Alive: A Teenager in the Belgian Resistance and French Underground is the incredible story of Mary Rostad's early life. Rostad was 16 years old when the Nazis conquered her home city of Brussels in 1940. She joined the resistance movement, serving in Belgium and later France, primarily as a courier of underground documents. At the end of World War II, Rostad met U.S. Army Staff Sergeant Allen Rostad.