In The Bronze Bow, when Daniel returns to the cave, what does he realize is missing?
After his grandmother's death, Daniel spends an extended period of time taking care of his sister Leah and seeing to affairs in the village. All the time, though, the enforced politeness and civility of the village grates on his nerves, and he becomes homesick for the bandit camp. After a fight with Leah in which he lets his emotions get the better of him, Daniel returns to the bandit camp, only to find that he does not feel as at-home as he remembered.
Daniel wandered about the camp, noticing a few new faces, trying hard to experience the elation he had expected to feel. Then he knew what was missing. He had been watching, all the way up the trail, for a motion on the hillside above, for a familiar welcoming figure to come bounding down to meet him. Ridiculous. [Samson] had something better to do than to sit watching for him after all these weeks. But why wasn't Samson somewhere about?
(Speare, The Bronze Bow, Google Books)
Samson feels devotion to Daniel, and Daniel realizes that his emotional ties to Samson are a large part of his love for the bandit camp. Without Samson, the bandits are simply a group of people who don't really care about each other. Samson's emotional displays are what Daniel was missing, not the bandit camp itself. This is reinforced when Samson returns and Daniel realizes how much he missed the former slave. Later, he is overcome with the memory of solidarity at Simon's feast, and starts to realize that his real home is in the village.