Herman Van Daan is a friend and business associate of Otto Frank. He and his family--wife Petronella and son Peter--are invited to join the Franks in their secret hideaway. The husband and wife argue constantly, creating tension in the cramped living quarters. Selfish and temperamental, Mrs. Van Daan henpecks her husband; he is a stubborn man who nonetheless contributes his share of duties. Their son is 16 years old and, though closer to Margot Frank in age, he becomes intimate with Anne, who is 13 when they go into hiding. Peter is more withdrawn and quieter than Anne, who eventually becomes discontented with Peter, particularly over the uncertain plans he has for the future. After the group is captured by the Germans, Peter and Anne remain friendly at the Westerbork concentration camp. They were eventually separated at Auschwitz. Mr. Van Daan died in the gas chambers there; Mr. Frank witnessed him being led to the chamber. Mrs. Van Daan also died at Auschwitz, though it is unknown if she died of natural causes or was gassed. Peter died during a prisoner march from Auschwitz.