One of the quests that are just a side-note, but I am curious as to how you complete it.

First, you spoke to Lara and hear from her that children are mixing medicines to "cure" each other, not all clear on really why these children are doing it, but I thought it was a nice fore-shadow for the disease that is about to wipe the town.

After having found that the "cache" that they have been keeping the medicines (a house near the "stairway to heaven") I find two half-animal children informing me the powdered medicine are gone.

What do I do from here is my question 0.o

Pick up the powder from one of the tables on the second floor - then eithrer return it to Lara, or keep it (reccomended).