Actually this has happened in my family, I'm sorry to say, or at least something similar. My nephew was born with Hydranencephaly so he had part of his brain but not all. We know he could hear, taste, and feel but we don't know if he could see. The doctor told us he would only live a year if we're lucky. He lived 4 months and I wouldn't trade the time we had with him for the world. But we were pretty much just keeping him comfortable until he died and if we had known ahead of time that there was a problem the mother might have aborted. But I'm glad we didn't know. They were the craziest 4 months of my life but I am so glad that I got to love that kid for as long as I did.
So I don't know if that's really an answer but I thought I would share.
So I don't know if that's really an answer but I thought I would share.