Eventually, Harry let them over to Grimmauld place. The fireplace was situated in Harry's office. Everything was a little cluttered in the Potter house and this room was no different. The desk and shelves were overwhelmed by textbooks, children's drawings, and odd souvenirs. They didn't leave very much room for Teddy to escape to when Draco finally let go of his shirt. However, the lack of potion smoke in the room meant that he finally got his cough under control. His lungs still had a raspy sort of burn-itch that twinged when he breathed, but at least he could breath now.

Meanwhile, Draco and Harry had fallen into their usual routine of exchanging insults. But between the insults, Draco was able to get his information across. From what Teddy could glean, the white potion suppressed a werewolves' transformation. Draco was convinced that if a werewolf couldn't transform on a full moon, it would die. He cited convoluted theoretical research that Teddy had never heard of before. Then he started talking about the preliminary experiments he had done back at his lab on Teddy's donated tissue.

Harry listened to all this with growing rage. Teddy didn't want to be around when Harry finally realized how much of this was Teddy's doing. Trying to keep his breathing quiet, Teddy backed towards the door.

"Teddy," Harry snapped and Teddy straightened, conditioned by years of having Harry as his surrogate father. "You let this madman experiment on you? How could you let him know about your secret?"

Draco snorted. "That he is a werewolf? I figured that out the first year he started changing. I'm not an idiot, unlike some people," -Harry glared at this- "and who do you think was polyjuiced as him at Hogwarts?"

Teddy froze. When he was back in Hogwarts, they had decided it would be less suspicious if someone took his place during the full moons. Harry had recommended Ron, but Ron wasn't a great actor. Teddy was afraid of what Ron might do or say in an attempt to convince everyone he was Teddy. So, without telling Harry, Teddy had asked his Uncle Draco instead. Draco had agreed more easily than Teddy had expected, making him a little uneasy. When Scorpius started acting like they were friends, Teddy relaxed a little. That at least pointed towards an ulterior motive for Draco. Then when the first year passed without any pranks or disasters, Teddy finally relaxed.

Even so, his friends had always said that Teddy was a jerk once a month. His girlfriend had teased that he had PMS and Teddy pointed out it was unfair that she got to tease him about something she would have tolerated from him. Still, Draco's probable prickliness was a small sacrifice compared to being replaced by his Aunt Ginny or, Merlin forbid, his grandmother.

Harry was still choking in disbelief. "Him- you? Hogwarts?"

Teddy was torn between trying to explain himself and bolting. Seeing Harry's wrath increase with each exchange, Teddy was pretty sure leaving was the safer bet. He started slipping towards the door again. Harry stopped him with a glare and an accusing finger. "You, we are talking about this later after I deal with him. Just know you are banned from Lilith's case."

Teddy forgot about his escape. "What? I- we just cracked it open and you are going to throw me off of it?"

Harry shook his head. "You're off and that is final."

Teddy returned to where his Uncles were standing and tried to argue the point. Harry wasn't listening and Draco didn't help. Draco did try, in his way. But Draco's snide comments about flexible Gryffindor morality seemed to incite Harry rather than do anything productive. Finally, Teddy had to give up and leave before things got even worse between them. Besides, he needed something for his cough.

…

By some miracle, Harry was eventually convinced that Hermione might be a werewolf and the potions in her system were probably killing her. Although Harry wasn't happy about it, Draco had been taken on as a medical consultant for Hermione's case. Teddy didn't expect that to go well and (sure enough) had heard second-hand about some of their public insult battles. However, within the week Draco and Harry developed a plan for healing Hermione. Teddy wondered how much of their fast work was due to their desire to be rid of each other.

In any case, it meant they could lift the time-coma at the next full moon. Then they would administer an antidote to the white potion that she had been given when she first entered St. Mungo's. Hermione, free of the potion's effects, would transform into a werewolf and stop wasting away. At least, that was the theory.

Draco had done more work testing the properties of the potions he had recreated and the antidotes he had created for them. They knew Draco's potions worked, at least to some degree. They had tried the antidote for the white potion on Teddy's tissue donations and then Teddy himself. Teddy's cough had lingered for days after the events at the Manor. Draco suspected it was from inhaling some of the potion that was killing Hermione. However, in the name of potion science, Teddy was fed both the antidotes that were going to be used on Hermione and then was subjected to a barage of diagnostic spells and potions. Teddy didn't understand half of it and wasn't interested in trying. When the cough resolved within a day, Draco seemed quite pleased and even Harry had to admit it probably was a good sign. Though Harry was quick to point out it was Draco's fault that Teddy had the cough to begin with.

Still, Draco didn't let anyone forget that they were dealing with a lot of unknowns. He initially had been reluctant to let any humans near Hermione during her change. After Teddy had admitted that the presence of humans tended to distress new wolves, Draco had been adamant about it. He was very clear that he didn't want to add anymore unneeded stress into Granger's system as it tried to equalize with all the potions and her new werewolfism.

Like most of Draco's other ideas, Harry had contested that they should leave Hermione alone. However, they ultimately compromised by allowing Teddy to stay since he was also a werewolf. Harry had been reluctant to allow Teddy back into the case, even for this little amount, but there were few alternatives. That didn't mean that Harry gave an inch on anything else, though.