Her diary describes, from a teenage girl’s point of view. the trying days of the war when Nijmegen suddenly became a city on the front line. On 20 September, Trees mentioned the bombing and fighting: ‘Spent the entire night in a bomb shelter in the woods on the Waalheuvel Estate: amongst screaming babies, sleeping children and broken-hearted fathers and mothers conversing. Many are from Nijmegen and had to flee burning houses riddled with bullets.’ Trees received all kinds of small hand-outs from the Allied soldiers who liberated Nijmegen, including cloth emblems and chewing gum. She used the gum wrappers and badges to decorate her diary.