No parent should have to go through the anguish of seeing a child suffer.

We cope with it differently.

Denial is a coping mechanism. It numbs the pain.

As it's such an extreme situation; I'm not sure what I'd do. I'd very likely also not point out the reality of what is going to happen; but squashing his mission to conquest something that may never happen isn't right either.

So could you tackle this from a different point of view?

Tons of research must have been done on this. Maybe you can start an 'awareness' campaign / group on FB to get support for her? Or blog? Or start a support network or join a support network in your area? That way you are not denying and you are helping the cause by being proactive in a different avenue?

Just a thought.