Bellatrix Lestrange had been working hard, brewing a potion that would enable her greatest desire to come to fruition. She capped the bottle that smelled of snake venom and power, dropping it into a hidden pocket of her robes. The Dark Lord had sent her to fetch supplies, as her entire family had fallen out of favour for Lucius's blunder and Draco's inability to kill the old fool, Dumbledore.
The old man was gone, though. He was dead, and had ever made the Dark Lord so happy. She went to the drawing room, her master sure to be there. He sat at the far end of the table, hissing softly to his snake. She wished she understood; that she had the same gift of Parseltongue.
"Bella," he said quietly, not removing his eyes from the snake. "Get me some tea, and find me one of Lucius's prized peacocks. I am thirsty, and Nagini hungers tonight."
"Yes, Master," she said before leaving the room again. Bellatrix first went to the yard, where sure enough, there remained three albino peacocks, the remains of Lucius's once large flock. Without a word, she aimed her wand and shot a curse at the bird, rendering it unconscious. Levitating it at wandpoint, she returned to the manor and made herself busy in the kitchen.
She made tea quickly enough, pouring a few drops of the potion that smelled of venom and power into the cup before stowing it away once again. Dragging the bird behind her, she levitated the cup ahead as she returned. "Shall I un-stun the bird before you feed Nagini, Master?" she asked.
"No, we need not cause a commotion this night," Voldemort said before hissing at the snake, which uncoiled and made its way to the bird. "Now, I have sent Severus to gather any information relating to when they will move the boy. As it has only been a week since Dumbledore was killed, we can expect his report two weeks from now. Find the Carrows and let them know that once the Ministry falls, I will have positions at Hogwarts for them."
Bellatrix turned to leave, hearing Voldemort take the first sip of the tea. "Wait," he said before rising. "Stand right there. The way the light reflects off you there is simply stunning. You look radiant."
Bellatrix smiled, hearing the words she had always wished to hear from the Dark Lord. It only took a little Amortentia to bring them out of him, after all.
"Thank you, Master. I –" she began, but Lord Voldemort held a hand up to silence her.
"Now, I have another task for you this night. Forget the Carrows, and let us go to your chambers..."
Nine months later, Bellatrix had just given birth to a healthy baby boy with the blackest hair she had ever seen, a purer black than even she had. She held her son and Narcissa looked on proudly.
"Congratulations, Bella. I can't believe that you have a son now!" she exclaimed, wringing every bit of positive emotion out of her mind and into her words. She no longer felt much pleasure at being Bella's younger sister, but had gladly taken on the role of godmother.
"Thanks, Cissy. I really appreciate your help, and He will certainly be proud. Rastaban Cygnus Slytherin sounds like a good name, yes?"
"Very. Papa would be proud to have a grandson born of the Dark Lord and named for him," she responded truthfully.
"Well, then, I suppose it's about time to introduce him to his father. I wonder why he isn't crying," Bellatrix wondered out loud.
"He doesn't cry," Lord Voldemort said upon seeing his son, upon seeing the dark brown eyes staring back at him.
"No, he doesn't, my Lord," Bellatrix apologised quickly. "I do not know –"
"Good. I could never stand the sound of a child crying. It's weak."
"I agree fully, Master," Bellatrix recovered, glad that he was not angry about this.
"I will be out of the country for the next few days. I want you to relay to the rest that no one, no one, is to summon me for anything less than Potter. Do you understand?"
Mere weeks later, Bellatrix Lestrange and Lord Voldemort lay dead, their son still resting peacefully at Malfoy Manor. Upon their family's acquittal, Lucius and Narcissa resigned to raise the child as a boy who would not hold the prejudices of his parents. If they could do that, they reasoned, they would truly be doing a service to the magical community and would truly be earning the freedom they enjoyed.