No, it's not that she has a twelve year old mentality or emotional development. That's just wrong.
The woman had early severe back injuries from horse falls and other things. She's had more than enough problems and more than enough drugs and pain.
It's not that she has a "stunted" mind as you wish to say.
That's just silly, Alia.
Okay, you are fond of her. That's good, BTS.
I find her boring, predictable, and pathetic. My mum would be so disappointed in how Liz has turned out.