Young Masbeth is the son of Masbeth, the fifth victim of the Headless Horseman. With the death of his father, he is now orphaned. His mother died not a long while before, and he has no other family left.
He asks Ichabod if he could become his apprentice, and help him track down the Headless Horseman. He was the chance to be able to avenge his father's death. At first, Ichabod declines because he doesn't really see how a child such as Young Masbeth could possibly help. But he finally says all right and Young Masbeth is now under the care of Ichabod Crane.
Young Masbeth is the first and only person who volunters to go with Ichabod into the forest to search for the Headless Horseman's grave. True, Katrina does show up later on just in time to find it, but Young Masbeth was the only one to truly stick up for Ichabod in front of the town's most powerful men.
Young Masbeth shows true courage in the face of danger and never once thinks about leaving Ichabod's side. He even offers to kill a spider for Ichabod after seeing how frightened he was of it. Aww....
When the Headless Horseman is chasing them, trying to get at ________ and get _______'s head, (I'm not telling you who it is!!!) he never runs or cowers. He always keeps helping and fights just as strongly and bravely as any of the townsmen. (And in most cases, more so!)