Which words from paragraph 8 help the reader understand the meaning of sinister?

When you consider the whole passage, you can see that the visitoe tried to mislead Mrs. White by saying her son is in no pain. The truth is he is dead but Mrs. White does not process this trick of meaning until later.

The visitor bowed in assent. “Badly hurt,” he said, quietly, “but he is not in any pain.” “Oh, thank God!” said the old woman, clasping her hands. “Thank God for that! Thank—”

She broke off suddenly as the sinister meaning of the assurance dawned upon her and she saw the awful confirmation of her fears in the other's averted face. She caught her breath, and turning to her slower-witted husband, laid her trembling old hand upon his.