I hope this doesn't come across offensive, as it's really not intended to be so.
I find Connie's insistence that Charlie can do these things they say he can, to be a tragic and deeply sad example of what we all know to be true of many mothers.
A 4 month old baby makes an 'aah' sound when handed a rattle:
"Oh Look! He said Ta! He is such a clever baby saying thank you to his Mummy!"
Or when people anthropomorphise their pets.
"Oh you can tell he knows he's wrong, he looks so guilty" or,
"I knew the cat had been up to no good, she had that look on her face"
Humans interpret emotions and actions in the only way we know how.
I think Connie and Chris so desperately want to attribute every little unconscious action as 'progress', that they really can't see the reality in front of them anymore.
A muscle twitch becomes 'he's trying to move', flickering eyes become "he can see", placing a toy in his little hand becomes "he's holding it", and the swelling of his body as it fails, becomes "Look at how well he's growing".
It's absolutely tragic.