"Tell her, there are 2 little girls (not so little now) who despite being disabled, went to Asia and set up NGOs and have done incredible things.". Oh there are two of them now are there? .
Em, I think so often disability has no variation to people. You are either disabled, or you aren't, iyswim? - to some people there is no concept of different types of disability, or even differing degrees of the same disability.
I also think that to some people, their ignorance is born out of their own inability to understand how they would cope in the same situation. i.e. people have often said to me "oh it's so marvellous, all the things you can do, it must be very hard to cope though?" when in actual fact what they're saying (indirectly) is "I know that I need to see to do x and y and z, so I can't understand how it can be done without being able to see." does that make sense? My disability is not so much of a disability to me, because I've lived with it all my life, and know no different, but to someone who has never experienced it, the prospect is terrifying.
This woman won't do her child any favours by degrading her life like that. I went to school with people whose parents hadd much the same attitude as her, and who grew up with far less independence, and far less abilities, despite the fact they have exactly the same disability as me, and are therefore capabble of exactly the same things.
You can only keep doing what you're doing, and knowing in your heart that you're doing the right thing. You will come across people like her throughout your life. some are worth educating, others will never take anything onboard, and sadly their children will pay the price.