"Listen," Snape said sharply, leaning forward in his chair. "I would beg you, as a friend of the family, to keep that sentiment to yourself in the future. Momentary lapse though it may have been." Hah. "Walls have ears, you know. Especially your walls." Not without reason, either. This made at least two of the Malfoys who seemed to be ready to subvert the Dark Lord directly, given the opportunity. It was worth making note of.
"Now, you guessed over a year ago why He took Draco into His service," he continued quietly. "It seems to me that His motivations in this case are personal rather than strategic, which, I admit, makes it more difficult for me to predict what He means to do now that Draco has failed." Probably the Dark Lord wouldn't have to do anything; the Malfoys were still distraught, which had surely been His intention. "Obviously, if there comes a time when I return to Hogwarts, I will continue to keep an eye on him for you to the extent that I can. For now ..." He paused. What now? "Now ... Have you ever had a - ah - 'momentary lapse' of loyalty in your son's presence? I assume he knows your feelings?" She's certainly made no secret of them to him, when she and Bellatrix had come to visit him they year before. "You must know I'm the Dark Lord's servant above all, but it would give me no pleasure to see either of you further ... disfavored."