How does Felix meet Zelda in the novel, Once?

While Felix is walking to the city, where he believes his parents are staying, a happens to see a house on fire. He discovers that all of the family’s chickens have been shot. A man and woman who apparently lived in the house have also been shot dead. Felix finds Zelda, a young girl, who is alive, but has been knocked unconscious. Felix takes Zelda with him because she no longer has anyone to care for her.