You state that the mother is delusional.

You base your diagnosis on her comment, "Had Charlie been given the treatment sooner he would have had the potential to be a normal, healthy little boy."

I do not think you have enough data there to judgmentally proclaim that the woman is delusional. That is a very harsh judgment of yours to make, in the absence of sufficient data.

I would be curious to hear the woman's response to this question: What do you think the odds would have been for a normal life if he had gotten treatment very early on?

If her answer was "50/50", then that would be evidence for your harsh accusation.

If her answer was "one in a million, but look, people win lotteries with worse odds", then no, that would not be evidence in support of delusion.

So I guess, unlike you, I will say simply that I have never walked a mile in their shoes and so I will give the parents of the doomed baby the benefit of the doubt on whether they are delusional or not.