Both the characters and the world which I am about to mangle belong to Rowling.
The man slowly comes down from where he had been levitating in view of the window to a certain infant's bedroom. It was utterly unbelievable. He had watched with a smirk as his master had stood in front of the child's crib having murdered the innocent's parents. His master had purposely taken out his wand and directed it at the baby. With a malevolent glint in his eyes he had calmly intoned, "Avada Kedavra". It was at that moment that the spectator felt an indescribable feeling of triumph as the light's last hope was struck by the pale green streak of light. That feeling was summarily obliterated as the streak of light reflected off of the infant's forehead and struck his master. His eyes widened and his mouth fell agape as his master's lifeless form hit the ground.
No! It was impossible, how could this child survive? How could his master be dead? It takes a few minutes for his mind to stop floundering with his new reality and attain some semblance of his cold and calculating personality. Despite what should have happened this child had somehow defeated his master with an unknown and completely passive defense. The child must be astonishingly powerful and this power will undoubtedly grow in time. He has no confidence that he could accomplish where his master had failed. The child would surely survive any attack that he could muster. The child wwill grow up as a beacon of the light and everything that he has woked towards will be undone.
He is suddenly struck by a moment of inspiration. Yes the baby is powerful, however perhaps he can harness that power. If taken and molded properly the infant could be changed from a beacon of light to a means to expand upon his family's power. It matters not to him that the infant was a halfblood. He is one of a surprising number of the Death Eaters who know that the Dark Lord is...was a halfblood as well. What truly mattered was the power and that it was used to achieve goals that coincided with his own. Having reasoned it out he comes to a decision and begins to put it into action.
He apparates to just outside of a home in a muggle neighborhood that he had previously scouted.. He pauses for a moment as he rememberes how many of his cohorts so often enjoyed the torture that they inflicted upon families that lived in homes quite similar to this one. He smirks as he considers how easy they are to keep satisfied. All he has to do is provide them the opportunity to delight in their brutish desires, prove himself their superior and the willingly follow his lead. His master, make that former master, had been an excellent example of knowing how to keep one's minions content enough that they would enjoy their service and yet fearful enough to not entertain some foolish notion that he was soft. He had soaked up all the lessons from observing the dark lord that he could. A part of his mind calls his attention to the fact that the same strategy that works upon his cohorts also worked upon himself. Of course he does not consider his own desires to be as brutish. Mindless torture simply doesn't do much for him personally, muggles are hardly worth his time unless their torture serves some additional purpose. The promise of more political power and wealth in a properly reshaped ministry, on the other hand, was quite enticing. Voldemort had been excellent at discerning an individual's true desires.
The house that he was currently standing in front of was a small muggle home of three with absolutely no connection to the magical world. He had dismissed it because no one would truly care about them, if he wished to incite fear in the magical community the parents of a mudblood made for a much better target. Their lack of connection made them perfect for his current plans. He transfigures a branch from a short tree in the yard into a knife with a six inch blade, casts a quick unlocking charm and enters the muggle home.
Striding purposely forward he hears the rustling of the sheets from the adult residents' bedroom. They have undoubtedly been roused from their slumber by his entrance. Opening the door he fires two quick stunners at the muggles before they are fully out of their bed. He then calmly walked over to the bed and plunged the knife into the man's throat, cutting laterally across his jugular. He then walks around to the other side of the bed and offers the same treatment to the man's wife. He then strides out of the room leaving the vermin to bleed out.
He enters their child's room and looks down at the sleeping infant. The infant appears to be nearly the exact same size as Harry just as he remembered. Yes, this will suit his purpose nicely. He draws his wand, uses the proper incantation, and watches as the green bolt of light leaves his wand's tip and strikes the infant. The small form enters a far more permanent version of sleep.
Apparating back to the Potter residence with the small bundle in tow he enters the home. Smiling at the dead James Potter he refrains from wasting time upon the deceased. As much as he may enjoy enacting some measure of revenge upon the corpse for the numerous times that Potter had bested him both in school and later on the battlefield he realizes that it would waste precious minutes. Besides, corrupting the last surviving Potter will be a far better revenge than mutilating a corpse. Continuing upstairs he spots Lily and cannot help but feel a moment of resignation. He knows that Severus's brooding will likely be intolerable for a considerable amount of time. After all, Severus is not particularly good at controlling his emotions even in the best of times.
Once he arrives beside the crib of his master's downfall he looks down into the disturbingly alert green eyes. Feeling a moment of trepidation he bends down and placed the dead muggle infant in the crib next to Harry. Later he would refuse to admit to feeling an unreasonable amount of relief that nothing occurrs except for the moderately loud wailing of Harry upon picking him up. Grimacing slightly he draws his wand and moves to cast a weak stunner at the child. Abruptly he stopps his movement as the recent death of the dark lord replays itself in his mind. Perhaps casting aggressive magic upon this one might not be a good idea. He decides to ignore the sounds, the screaming can only dangerous if someone arrives before he leavesthe premises.
After pocketing his wand he steels himself for the next task at hand. Struggling with a feeling of fear he kneels down and awkwardly pries the dark lord's wand from his dead master's hand. Returning to the crib he casts a few burning curses at the corpse of the child and crib to ensure that the form will not be distinguished from Harry's. He then casts the killing curse once more so that priori incantem will show it as the last spell to have been cast from the dark lord's wand. Returning the wand to the dark lord's hand he then turns and swiftly leaves the Potter home and apparates to his own mansion.
Pausing at the entrance he called out to Dobby. After the annoying servant appeared he hands the still screaming infant over and commands, "Dobby, take this child and care for his needs for the time being. Treat him as you would Draco but do not allow Narcissa to see him for the moment. I will likely call for you shortly at which time I want you to bring the child along with you."
"Yes master," the house elf softly replies before vanishing from his master's sight. Lucius stands there for a moment briefly pondering his actions. He hopes that he has covered all of his bases. Finally he acknowledges that he has done as thorough of a job as is possible for him to do. The groundwork is nearly complete, all that is left is to make Harry Potter an official part of the Malfoy family.
A few rituals used in the case of adoption will make him fit the appearance and there is a convenient Malfoy tradition that will make this all the easier. Malfoy women stay sequestered in the home from the time that they enter the second trimester until their child reaches the age of two. Other than their servants, children, and husband only immediate female family members are allowed to visit them. In fact the child is not even discussed to anyone else until after this point. Most families, even ones that you're aligned with, consider this practice to be archaic. The reason that this practice is continued in his family is because at the age of two the magical core is developed enough to be detected by a certain dark ritual developed by an ancestor. There is a reason that there has not been a Malfoy squib in over twenty generations.
It is for this reason that the only people to have seen Draco are Bellatrix, Lucius, Narcissa, and Dobby. Lucius allows a smirk to form as he realizes that although he is confident in his skills to avoid the punishment for his crimes he has suddenly become far less confident in his ability to protect his wife's sibling. The last thing that he needs is for her to begin speaking of how Draco's brother seemed to suddenly pop into existence. Having decided things in his mind he enters his home and sets out to find his wife.
He finds her in their library, facing away from him as she feeds Draco who is residing comfortably in her arms. Steeling himself for a probable confrontation he begins walking towards her. "I do enjoy the sight of you with our lovely child in your arms."
She turns around and regards him with pleasant surprise. "Lucius, why the sudden charm? It is rare to find you in such spirits after your typical nightly activities. I believe that I'll have Dobby care for Draco while I allow you to care for me." Her expression has slowly grown more predatory with her speech.
He isn't surprised by the response but decides to slightly modify his approach. The demands of a sequestered life tend not to agree with Narcissa. She attempts to keep herself occupied with studying and caring for Draco but it is a limiting existence. Her seclusion is the source of many arguments but it also leads to him being quite pleased with her endless desire to experiment with new things to alleviate her boredom.
She calls for Dobby and the elf appears. Lucius is glad that the elf remembers his orders and does not appear with a certain infant in his arms. After both babe and bottle are handed to the elf Lucius casually tells him, "If you need any additional help most of the other elves are unoccupied. Feel free to obtain their assistance."
She turns to him with some slight suspicion, "Dobby takes care of Draco frequently, I doubt that he needs additional help."
He playfully responds, "Perhaps I simply wish to be doubly sure that nothing disturbs us tonight." The elf disappears with Draco in his arms.
They share some expensive wine over a small dinner which Lucius has a separate house elf prepare them. Afterwards he tends to his wife's desires in all the ways that he knows she likes best. As he has grown older he has found that there are many applications of magic that are not covered in a Hogwarts education.
As they lay in their bed he turns towards her pleased to see the content smile that graces her face. "My blackest desire, I have something which I must share with you. I hope that you will consider what I am about to confide in you with all of the cunning that your incredible mind possesses." He loves the way that her face transforms to an utterly blank mask as she regards his words with growing suspicion. As Lucius utter his name Dobby appears with a sleeping dark haired infant in his arms. "My love," he begins, "I would like to introduce you to Draco's new twin brother." It speaks to her character that no confusion clouds her face.
A/N:This is my first fanfic so feel free to tear it to shreds. Hopefully it'll help me grow. I'm going to show the Malfoy family as one that actually cares about one another. I honestly think that this is entirely in character and as far as them being more tender towards one another, this is in the privacy of their own home. They are unlikely to exhibit this behavior in public. Couple notes about Lucius's character in this. I'm playing him as a bigot as he is in the series however in my story he does not hate muggleborns or muggles. He views muggles as insects that are unworthy of such emotion from him. He doesn't care if they die or are tortured but neither does it bring him joy. He feels similarly about muggleborns but realizes that some have the potential to be useful to him.
If a muggleborn is foolish enough to be his tool he's perfectly willing to use them and discard them if he believes he will have no future use for them. Narcissa will most definitely not be a saint either. Harry's personality will obviously be drastically affected by this upbringing and be further changed by future events. Having a brother will likely change Draco to some extent as well. It most definitely will not become a Draco/Harry fic. I typically despise this pairing(notable exception is lightning on the wave's series) and I truly suck at writing romance in general. I don't have too clear of a picture over what direction Harry will end up going. Its inevitable that he will display a marked degree of the typical pureblood bias but at some point I want to bring him back to the light. I am unsure of how I'll accomplish this so it could be possible that he might end up as evil!Harry as my characters tend to surprise me. He'll probably be a touch manipulative/scheming regardless though. I do need some help coming up with a new name for him until his true identity is uncovered. The name needs to be one that is plausible coming from Lucius/Narcissa. My current ideas on this point suck: Regulus and Phineas. Please save me from Narcissa wishing to honor her deceased relatives.