Character Analysis
Poor Ed Sansom, Joel's father, doesn't seem to know what hit him; neither do we, really. He's a mysterious figure at first, populating Joel's wild imagination. He fantasizes that his father, whom he still hasn't met, is spying on him:
And his father thought: that runt is an impostor; my son would be taller and stronger and handsomer and smarter-looking. (1.2.49)
At the beginning of the novel Mr. Sansom is really just a figment of Joel's imagination; we don't know anything about him.
The truth is, unfortunately, much worse than a spy dad. Ed Sansom is paralyzed. When Joel finally meets him, all he sees is a pair of eyes:
The eyes were a teary grey; they watched Joel with a kind of dumb glitter, and soon, as if to acknowledge him, they closed in a solemn double wink, and turned… so that he saw them only as part of a head, a shaved head lying with invalid looseness on unsanitary pillows. (1.6.20)
Ed's a prisoner in his body and at the Landing and he is only able to communicate by dropping red tennis balls on the floor so that they'll roll downstairs and get someone's attention. He can only get a few words out like "kind boy" or "bad boy." This limited communication means that we can only guess the horror he must feel at what his life has become.