I'm not feeling well, which is one reason why this chapter is coming out a bit early. If there are errors in this, typos or otherwise, I'll get to them when I'm feeling better. My notes this time will be brief, not only because I am sick but because this chapter is somewhat shorter than usual.

It might be obvious to most if not all of you reading this that the title of this story is a reference to the Butterfly Effect—that is, the smallest of events can set the biggest into motion; a butterfly flapping its wings on one side of the planet can cause a tsunami on the other. It's a nice metaphor for what I'm doing here, I think, and has been a driving theme of the story so far.

That said, the butterflies are beginning to fly.

Enjoy.

One.

"You little worm!" a female voice screeched with all the trappings of absolute insanity. "Vile betrayer! How dare you show your face to me? How dare you touch me? I should kill you where you stand!"

A male voice, quiet and nervous and not at all used to tones of command, nonetheless tried: "…If you like, I c-can…call Moody back here, and you can t-try your luck with…him."

"You threaten? You? What stupidity is this? What trick? Do you think you can…do you truly think that you can intimidate me?"

"He's caught your husband." The male voice gained in confidence when the female voice did not reply. "He's caught your brother, and Crouch. They know you were with them. S-Sirius and Remus know. Dumbledore knows. They'll be…looking for you."

"They were already looking for me." A scoff that wasn't as confident as it should have been.

"If not for me, you would be with them. And even you can't handle Alastor Moody, especially with other members of the Order with him."

"So I owe you now. That is what you mean to say to me?"

"You…owe me courtesy. Betrayer? No. Something else was protecting the boy. I had nothing to do with what happened to His Lordship. I did what no one else could. I showed them to him. I delivered them to him. If they had extra defenses that no one saw fit to tell, how is that my betrayal?"

Suspicious. Angry. Almost sulking. No reply.

"We…you and I…know better than the others. We know he is too strong to die. The others…the others are ignorant. Let us find him. Let us bring him back to us. We'll show His Lordship that we, and no others, are loyal."

Where had this come from? Loyalty? The owner of those words did not know. Some part of him thought that he knew, better than anyone, what Severus Snape knew: good fortune could not be trusted. He was not dead. The Dark Lord was eternal. They had sold their souls, and salvation was too good to hope for. So why pretend? Why hope? Why not, instead, use the time? Why not use the opportunity?

With this woman in front of him…it made sense.

It seemed the most golden chance he could ever hope for.

The woman's eyes seemed to drink in the idea, and he knew he had won her.

Bellatrix Lestrange let a savage little grin spread on her lips. "…You speak truth, Wormtail. Fine, then. Show me that you have not betrayed our master."

Peter Pettigrew did not believe that this woman's approval was anything to be proud of, but it was better than nothing. He said, "We know there is a spy in our midst. We know that information has reached Dumbledore. The Order found you. It nearly found me."

"First order of business?" Bellatrix asked. "Find the spy?"

"Something like that," Peter said. "What say we turn the tables? Instill a spy of our own? They're searching for me. They want to find me. They want to know where I am, and what's happened to me. Let me go back to them. Dumbledore will never believe that His Lordship is gone until he has proof. He'll keep searching. Let him do our work for us."

She looked suspicious again. "It sounds to me like you are finding an excuse to scurry back to your old friends, Wormtail."

"Tell me you wouldn't use Sirius, if you thought you could," Peter returned, unable to keep the nervousness out of his voice at the murderous fire that lit in Bellatrix's eyes at the sound of that name. "These are resources. We can use them, the same as we did when His Lordship was with us. Use them to find him. Let them think we seek to kill him."

"…I do not yet trust you, Wormtail." There was a long silence as she considered him. "Go, then. Return to your Order. Play the victim, and let them think that you have escaped us." The grin returned. "But I must play the part, don't you think? It won't do for them to think I do not target you, the same as I do them. After all…you speak of returning to the enemy."

Peter's hope of getting out of this unscathed sank into his shoes, and he quailed. "B-B…Bellatrix…?"

"How else could your secret have come to us?" Bellatrix continued, her face flushed with fever. "How else could we have convinced a loyal member of the Order to give us information? The Dark Lord must have tortured the information out of you. If you come back to them in good health…well. That won't seem very convincing, will it?"

What color remained in Peter's face disappeared.

Bellatrix caressed her wand lovingly. Seductively. "Let us see how brave you are…Gryffindor."

Two.

It wasn't unusual for Sirius Black to be sitting in the Headmaster's office at Hogwarts. He had made it a school-time mission to break at least every written rule once per year. The strange part was for him to look sorry.

But there he sat, dejected and restless, hands dangling between his knees and his head down as he stared at the floor. His curtain of black hair covered his haggard face. When Harry reached over and grabbed hold of it, cooing curiously, the smile that spread on Sirius's face looked much more like a snarl.

Neville was hitting the floor with a toy wand, gurgling as though intent on casting a spell. When this didn't work, he swung harder, and it bounced out of his hand. The youngest member of the Longbottom family stared openly as his toy struck the wall and clattered to the floor, then threw up his arms like he'd won something. Harry looked up at Sirius, perhaps trying to figure out what was going through his godfather's mind, but eventually gave up. He went back to Neville and began embarking on a conversation that only the two of them seemed to understand.

Dumbledore walked in some time later, Augusta Longbottom looking stern but pale just behind him. Sirius glanced over at them. "Kids are all right," he murmured. "Don't seem to know anything's…wrong." This report delivered, he trailed off and turned back to silent musings.

Augusta sat down in an empty chair near Sirius, a rare smile rising on her lips as she regarded her grandson. Dumbledore stepped over to his desk, took his imperial seat behind it, and tented his fingers in front of him as he looked at the both of them. When he spoke, he sounded as calm and collected as he always did, and went about the business of discussing the attack on Hollinwood Hill the same way he would have delivered a start-of-term speech to his students: "Frank and Alice have been transported to St. Mungo's. Alastor tells me that he has managed to capture three of the four Death Eaters responsible for this." He locked eyes with Sirius. "Bellatrix Lestrange remains free."

Sirius grimaced, but did not speak.

"Before I go further," Dumbledore continued, still looking at Sirius, "I would like you to give me a full account of what happened last night."

The last Black was used to telling half-truths in this office. It took him a long while to decide that it wouldn't do this time. With a spasmodic glance at Augusta, he began to talk. He told them everything, starting from his apparition and ending with his arrival at the old castle that had been his only real home.

"How long have you been able to transform into a dog, Sirius?" Dumbledore asked calmly.

Sirius stared at the man. "About five years, give or take."

"It will take some doing," Dumbledore replied, cool as ever but with a certain edge to his voice now, "but I believe I should be able to smooth things over at the ministry and keep you out of Azkaban. I must ask that you undergo registration, however. You understand this."

Eyes narrowing, Sirius said, "I'd hoped to keep that information private."

"Then you might have refrained from showcasing your ability in front of four prominent Death Eaters," Dumbledore replied offhandedly. "Your status as an Animagus will no longer be private, I'm afraid, no matter what you or I have to say on the subject." He now turned his attention away. "Augusta," he said, "I trust you will be able to look after Neville while his parents are being cared for."

"Of course."

Silence.

"…Missus Longbottom," Sirius finally said. "Ah…" All eyes were on him now, even Neville's and Harry's. He fidgeted, let out a disgusted sigh, and stood up. He bowed his head in deference to her. "I wanted to say…I'm sorry for everything. The way I acted, I may well have killed them. There's no excuse for my…" he seemed to be searching for the right word, then settled on "…recklessness. I hope that you can forgive my stupidity."

He raised his eyes after a moment, daring to look at the woman, who was studying him. Augusta's face was unreadable. Her mouth twitched, and she finally stood up herself. Sirius went stiff as she wrapped her arms around him and pulled him into a hug. "Stupid child," she said shakily. "Were it not for your stupidity…my son, my daughter, and my grandson would be dead."

Dumbledore was last to stand.

He said, "Quite right. But do well to remember what Alastor and Remus have told you: you are fighting for more than one life now. In every decision you make, and every battle you take part in, you must think of Harry. Remember, as I am sure you will, that you are now his only parent."

Sirius glanced down at his godson as Augusta stepped away and gathered Neville in her arms. Sirius sighed, reached down, and picked Harry up, looking at him quizzically. "You're going to be the death of me, boy. Do you know that?"

Harry grinned at him, as if he understood and found it funny.

Sirius let out an involuntary chuckle, and stole one last glance at Augusta as she turned to leave; she gave him a conspiratorial, and thoroughly out-of-character, wink.

Three.

The next time Remus Lupin saw Sirius and Harry, they were hunched over on a riverbank in the middle of a Muggle campground; Sirius was washing something, while Harry played with the water, every so often splashing his godfather and giggling.

Sirius was bare from the waist up, and as Remus approached, he realized that the man was scrubbing a shirt. "The next time you throw up on me, I'm returning the favor," Sirius growled, "and keep your distance, would-be-Remus, until I have a chance to indulge paranoia."

Remus stopped moving, his stance easy and his hands slipped into his pockets.

Sirius finally stood up, spread out the soaking shirt, looked round, and groaned. Sighing, he wrung the garment free of excess water and tucked the end of it behind his belt, letting it hang against one leg. He turned, wand in hand. "All right," he said, "quiz time: who's my least-favorite relative?"

Remus raised an eyebrow. "You don't have one. You keep telling anyone you can that you choose family, and related to anyone you damn well like."

Sirius relaxed. "Not much use hiding if it's so easy for people to find us," he remarked. He glanced down at Harry, and picked the boy up before he went head-first into the river, as he'd been reaching for a particularly shiny rock. Kneeling down, Sirius picked up the rock and handed it to his godson, who squealed with delight and promptly put it into his mouth. "Oh, for God's sake!" Sirius rolled his eyes and plucked the offending object out of Harry's reach. "No," he said, as though speaking to a pet, when Harry made a desperate grab for the rock. "No. You hear me, brat? You don't. Eat. Rocks." He scowled, trying to look menacing. "Say it. 'I don't eat rocks.' Say it, boy."

"Dun…ee…wah," Harry declared.

Remus snickered loudly, covering his mouth with one hand. Sirius did no better, grinning outright and handing the rock over. "I'll let you off with a warning this time. Manipulative little snot." Harry waited until Sirius was looking at Remus, then began inching the rock toward his lips.

"Harry," Remus said, his inflection rising. Harry blinked, then tried to hide his bauble behind his back. Sirius glared at him, clearly suspicious.

Harry stared innocently at him. "Dun ee wah," he repeated.

"I'm watching you," Sirius warned.

"Where are you camped?" Remus asked after a while.

Sirius gestured. "Just back there. Borrowed a Muggle tent from Arthur on the way here." At Remus's searching look, he added, "What? Can't be too cautious. We're trying to blend in, right? Besides…feels like cheating otherwise."

"How rustic," Remus murmured.

"Let's go," Sirius said, shifting his grip on Harry so that the boy was hanging over his godfather's shoulder like a sack of potatoes. Remus took the rock from Harry's mouth as he fell into step beside them, and slipped it into a pocket.