Ronja manages to create a small opening in the rubble and soon hears a whistled tune. Recognizing the song from when Birk whistled it, she begins whistling it back. Birk then calls out unseen to her from the other side and Ronja asks if he meant he would be her brother; Birk responds that it is good to hear his sister's voice and it'd be nice to see her. Their conversation is cut short when Ronja hears someone down below with her and says they'll talk tomorrow before running off. The next morning after Ronja and Mattis endure a lice combing from Lovis, Ronja heads back underground with some provisions. She is startled by Birk who's been waiting for her on the Mattis Robbers' side of the rubble and Ronja is surprised to see him pale and thinner. She learns that the Borkas Robbers are low on food and won't last until spring. Ronja offers Birk a loaf of bread which he wolves down with eagerness and drinks all the milk. Ronja decides to visit Birk every day during the winter to give him food. Birk and Ronja swear to secrecy, though they hate it, knowing how enraged their fathers would be to learn of their friendship.