Proof that the victim who wrote the journal and the victim with mosaic down syndrome are the same?

Someone posted about this several days ago. I asked where it was stated that these two victims were the same person. I also asked on another thread where the same claim was made as well… and nobody ever responded with information proving they're the same victim.

I'm curious if they're actually the same victim or if someone just came up with that theory and everyone took it as fact.

Can anyone share sources proving they're really the same victim?