"If you only cleared the house, you'd be quite happy, wouldn't you?" said Herbert, with his hand on his shoulder. "Well, wish for two hundred pounds, then; that'll just do it." (1.55)
Next to food and love, what is the number one thing a family needs? A place to live, right? The Whites, we learn here, have to pay the bank every month or they will lose their home. Notice that it's Herbert bringing this up. Since he's the one working, it's probably up to him to make this monthly payment. Although he seems cheery about it here, it probably causes him a lot of stress.
"He was the only one left to us," he said, turning gently to the visitor. "It is hard." (2.23)
These two brief sentences from Mr. White reveal that Herbert was not their only child. We aren't given any details beyond this, but the point is made: the Whites have been through this before. They have now outlived <em>all</em> their children.
It was all over so quickly that at first they could hardly realize it, and remained in a state of expectation as though of something else to happen--something else which was to lighten this load, too heavy for old hearts to bear. (3.1)
These lines foreshadow Mrs. White's crazy plan to use the paw to put what's left of her family back together again. Do you think Mr. and Mrs. White will ever be able to find happiness again? Can they find comfort in each other?
"Bring him back," cried the old woman, and dragged him toward the door. "Do you think I fear the child I have nursed?" (3.25)
Have you ever wanted something so badly that you ignore the risks and just focus on the possible benefits? Mrs. White misses her son so badly that she doesn't think about the fact that his body was, as Mr. White points out, horribly mangled and has been dead for ten days. If Herbert comes back like that, he may be pain. If you've seen any zombie movies, you know he'll also probably be murderous and maybe even hungry for human brains.
"You're afraid of your own son," she cried, struggling. "Let me go. I'm coming, Herbert; I'm coming." (3.45)
Mrs. White isn't being fair here, and Mr. White is able to see clearly enough to recognize this. He has learned his lesson about wishing hastily. He can see all the problems that undead Herbert might bring.