In spite of Lily realizing the risks she had been putting herself and her child in, Severus could not help but to warn her. He cared for her, loved her, even though it wasn't exactly returned in the same fashion. Severus did not particularly want anything to do with James, yes, but half of the blood that ran through those very veins of Harry's was essentially Lily's, and Severus, dismissing the idea of his allegiance toward the Dark Lord, would thus lay his life, talents, and abilities down for such. It didn't necessarily help that Severus also owed James his life after being rescued from the wrath of Remus' wolf-like interpretation. Whether or not he truly believed that it was an attempt to win over Lily's heart, Severus still felt such debt was long since overdue. When Lily offered sarcasm to quickly brush off his comments, Severus narrowed his brows and proposed an expression of refusal. “I'm sure you could have envisioned something less costly.” Fingers pushed through those clammy strands of hair, as he scowled down at the infant that seemed to be resting peacefully in his mother's arms.
“I will not lie to you,” started the potion enthusiast, “You had asked for a strong brew and so a strong brew I have produced. If my calculations are correct, it is 19 times more effective than an original Polyjuice; it will last longer and the sudden alteration in appearance will be nearly impossible to identify,” Severus motioned toward a knapsack that had been dangling at his waist before revealing to her a small vial that contained a murky-colored liquid. “It is vital that we assess the right dosage. A transformation such as this can be harmful indeed, depending on such articles obtained for said transformation, in which to be applied to a child this young in age.” He lowered his head and gathered a spoon utensil from one of the kitchen tops she had been sitting beside. “As you can already tell, many Polyjuice serums are coarse in nature. Though, I have added a viable ingredient to alleviate any pain as the potion enters and departs from the infant's diaphragm.” Through the candlelight, Severus filled a small bottle partially with milk.
“I suggest we add a fourth of this glass vial to the bottle of milk here. In my expertise, you mustn't feed him no more than a diligent course of fourths at a time, Lily.”