It can take some time for a chicken to recover, just keep treating as suggested earlier and add the much needed calcium.
When did your father last deworm them and what did he use for how many days?
Here is what I would do:
#Prepare a tea with fennel, thyme and oregano and let it sit for at least one hour before serving instead of water.
Prepare fresh every day.
#Feed her some scrambled eggs with rolled fine oats and millet adding half a tablet of vitamin B complex. In case she refuses to...
For 8 months old she looks rather pale.
Since when does she lay eggs if at all?
I can hear a gurgling sound in your video, does it stem from her?
How does her poop look?
When did you last deworm? If you haven't already this would be the first thing to do.
Did you recently add new birds to...