By the end of that summer Rose and Savin were aware that things would likely not remain as they were for long. Snape had warned them that his Dark Mark was getting clearer for the first time since Voldemort's defeat, and the events of the Quidditch World Cup helped confirm that something was going on (not that Rose, Savin, or Snape had attended the match, none of them having much interest in the sport, but the news of the chaos that ensued that night, and the presence of Voldemort's mark above it all, spread like wildfire through the wizarding world). Even Snape, with at least a few contacts on both sides of the issue, had no way of knowing exactly what was going on, or when things might begin to really escalate, so no immediate plans could be made, but the entire Aurum-Snape family was wary and on their guard, and Snape found himself even more grateful that Rose and Savin had turned down his offer to live at Spinner's End. He hoped that he was wrong, that this was not the foreshadowing of the Dark Lord's return, but instead just something cooked up by former Death Eaters, but whatever it might be he knew his children would likely be safer the farther from the situation they could get, which might come down to keeping them as far from himself as possible to avoid letting them get mixed up in things.
There wasn't much danger of anyone seeing Rose and Savin with Professor Snape during that school year. He was off at Hogwarts, and with all of the preparations required for the Triwizard Tournament, and the event itself, Snape had even less time than usual for going home or meeting up with them. They heard plenty of the older man's thoughts by letter, though, angry musings over what on earth had possessed Dumbledore to try to bring back the Tournament, especially at that time, and even angrier about how Harry Potter had ended up entered into the competition (here it was somewhat hard to tell whether he was more upset that someone had entered the boy, that it wasn't known who had entered him or why, or that he was being allowed or maybe forced to compete anyway), interspersed with warnings about the darkening of the Dark Marks (not only his own, but that of Karkaroff as well), and slight concern over why Dumbledore was allowing the Auror Mad-Eye Moody to harass him, which seemed somewhat out of character for the Headmaster.
All together this certainly served the purpose which Snape probably intended, that of making sure that Rose and Savin were being very careful and on the lookout for anything odd or unusual in their trips through the Alleys. Working as they both did farther into the Wizarding Alleys than Diagon or even Knockturn, the pair did have the opportunities to hear the gossip of the other people who lived and worked in these areas, and passed along the rare useful pieces of information to Snape, who passed them along to Dumbledore. There wasn't much, mostly just the same growing fears and worries that plagued most in the wizarding world at the time, particularly among those who had lived through Voldemort's first reign of terror. Most might not have any reason to think that Voldemort himself was going to come back, but even an uprising of those of his followers not in prison would be an unpleasant turn of events for the common folk (those who didn't support the idea of such a rising themselves, of course).
By the time summer came around again, all of the fears and concerns proved founded when Voldemort returned at the end of the Triwizard Tournament. While some in the wizarding world clung to the belief that it was all a lie, that everything was fine and Voldemort certainly wasn't alive, well, and killing people, Rose and Savin knew better. They would have believed Dumbledore and Harry Potter's tale regardless, but they had the additional witness of Snape himself. They had been at home the night of the third and final task of the Triwizard Tournament, not doing anything much in particular, when they received a patronus message from Snape, sent just before he went to find the newly reborn Voldemort. In it he quickly and succinctly informed them that the Dark Lord had returned and he had been called upon to resume his spying activities for the Headmaster. There was a slight hesitation in the message there, as though the sender had paused for a moment before deciding how to proceed, and then the rest came out slightly more rushed, in a flat voice that Rose recognized from when Snape had begun teaching her and Savin Occlumency a few years before, the voice of a man who had completely shut away any and all emotions before continuing to speak. In that flat voice, Snape told his children that he was leaving the necklace they had made him, along with a letter, with the Headmaster in case he did not return, and that they should not try to come after him or go to Hogwarts unless summoned. There was no goodbye at the end of the message, nothing to mark that this could have been the last message he would ever send them, only a moment of silence before the silver doe of Snape's patronus dissipated in the air.
Neither Rose nor Savin had been expecting this exact message, but they were not caught as off-guard as they could have been. Snape had told them long before of his suspicions that Voldemort was trying to come back, as well as warning them that if such a thing did come to pass he would have to go to him, to try to spy again if he could. None of them ever spoke aloud the thought that all three were very aware of, that there was a very good chance that such an attempt would be unsuccessful, and would end in the professor's death at the hand of his former master. Knowing a thing might occur was a little different than knowing it was happening as you stood there, unable to do anything to help or even to know what was going on, and Rose and Savin became ever more concerned as the hours passed, waiting for some news, for good or ill. It was many hours later that they received any word at all, long enough that Rose was beginning to talk of going to Hogwarts to see Dumbledore despite everything that Snape had said, which Savin repeated back at her while himself still clutching at the pendant around his neck, as though hoping it could give him word of Snape even while the other man didn't wear his own linked pendant. Not that Rose was in any position to judge on that front, she was holding to her own necklace no less tightly. Just before the point where Savin almost did give in to Rose's suggestion, at least to send a message to the school if not going themselves, an owl came tapping on their window. It carried a folded piece of parchment with a few short sentences written on it in handwriting that both of them recognized as Dumbledore's: "He is safe, though injured. Do not come."
Despite the temptation to disregard the Headmaster's orders and make haste for Hogwarts, they instead remained in the apartment, though neither even bothered pretending that they were going to go to sleep without any real information. Not too long after that, both of their necklaces suddenly pulsed slightly, growing just barely warmer as they reestablished a link with the pendant on Snape's necklace, which he must have just put back on. Savin relaxed slightly, relieved by the confirmation that the potions master was alive and well enough to put the necklace back on himself (for it seemed unlikely that the secretive man would have wanted to let anyone else know how important the piece was to him), though Rose seemed a little frustrated when no message followed the initial pulse. Finally, after what felt like an eternity, but probably was no more than another half-hour or so, a real message did come through the necklace pendants, Snape's tired voice telling them that he would be fine, and would try to meet them somewhere the next day, as soon as he could get away from Hogwarts. While not exactly all the information that they were looking for, it was clear that it was all Rose and Savin were going to get for the time being, and with their worry for Snape diminished if not necessarily gone, the pair went off to try and catch at least a few hours of sleep, hoping that the news the professor would bring the next day would not be as bad as they suspected it would.
Unfortunately, though unsurprisingly, that wish would not be granted. Voldemort was indeed back and gathering his scattered Death Eaters, and while he had ultimately accepted Snape's explanations and excuses and allowed him back into the fold, the Dark Lord certainly still had his suspicions, and the task of spying on him would be even more dangerous, and likely painful, than ever before. Beyond that, Snape brought warnings for Rose and Savin to be even more careful. As a muggleborn and a disowned pureblood (the epitome of bloodtraitor), they had every reason to believe that they could be targeted by Death Eaters as they regained more of their old power. In some ways, though, Rose and Savin were safer than most. They were living in muggle London, and had few immediate contacts in the wizarding world other than Snape and their respective jobs, which would make it more difficult for any Death Eaters to track them down. Even their jobs, located in the back alleys rather than on Diagon itself, would be more difficult to trace them to than if they worked somewhere higher profile, such as at the Ministry of Magic or even Hogwarts.
Their case was also helped by the fact that few people knew of their connection to Snape, so it was unlikely that they could be used against him, or him against them. It was well-known in pureblood circles that the former Silther heir had run off with a mudblood and been disowned (or at least well-rumored, which was almost the same thing), but the identity of his bride had never been anything the high society gossips had cared much about, and few purebloods enjoyed talking about that sort of thing for very long. Similarly, few people had ever been aware of Rose's adoption by Snape outside the professors of Hogwarts, who had no reason to make it public knowledge and every reason not to, and it certainly was not something that the Death Eaters would have easily found out. What might have been the most obvious way for Voldemort and the Death Eaters to learn of the existence of Rose and Savin and their connection to Snape, Snape himself, was in truth one of the least likely for their secret to be discovered. Snape was a master of occlumency, and had proven once again the night before that he was still more than a match for Voldemort's legilimency, able to not only withhold information, but more importantly to not let on that any information was hidden. He had done his best to teach Rose and Savin to do the same, but neither had the same inborn talent for the art, and while they were quite decent at it, likely better than most who attempted to learn, they certainly would be no match for a master legilimens. As a precaution, though one which she acknowledged was unlikely to provide much help if someone already discovered a connection, Rose did decide to return to using only her original last name, dropping the "Snape'' until the conclusion of the war, to avoid anyone new discovering the connection and using it against any of them.