Again I mention my conviction -- almost unsupported by the text, but there between the lines -- that Decoud's sister started the Monterist war, by betraying Decoud's gun-running operation to the Monteros. What else is the meaning of these glimpses of her character -- "arbitrary," "resolute" -- except that she is capable of switching sides in pursuit of a goal? The word "ruling" here implies that she financially suppports the Decoud parents (in a "very fine Parisian house"), suggesting at least one possible motive for selling out Ribiera. Decoud's confession of the plot to her and mention of Montero , and Pedro's earlier presence in Paris , contributes to the plausibility. The "first-floor apartments" here could conceivably be symbolic, meaning that the Decouds got in on the "ground floor" of the Monterist revolution. Finally, if the sister was a perfect friend it would go against the grain of the novel, in which everyone has their own interest, and in which one prior correspondence from Costaguana (Mr Gould's) has already led to betrayal.