Originally Posted by David
I would not be surprised then if it becomes Killua's solution to free Alluka from Nanika's curse.
Healing Gon will either kill Nanika -without killing Alluka that is- or put it to sleep for several decades, in both cases Alluka would be freed from the curse for her lifetime.
But that's really too convenient for Killua and the story, so I guess it should be a little more complicated than that.
Also, I guess Killua has to wait for someone to wish something, before he wishes to heal Gon.