Doctor says Tom was killed by some one beating his head in with a hammer or something of the kind.

Now who beat his head in?
Who would be most likely to beat his head in?
Not me, for we were mates.

Some one that hated him.

Some one that he was always quarrelling with--" Her face had grown so white that there was no colour even in the trembling lips.

She stared at him with terrified eyes.
"You know who I mean," he said.