I would also look at it individually, as opposed to saying that there is a specific increase.
However; I am surprised that the parents don't have funding for specialized care? I don't know the whole scenario, obviously. But I am also in AB, and most parents of special needs kids that I know receive a fair amount of government income to allow for an aide/assistant who is trained.
Perhaps the parent don't want to do this, but is there an avenue for her to be "learning" some coping methods, how to read braille, etc? I am sure you are a very capable provider, but much of that type of stuff is pretty specific.