First one likes to sleep all day. Second and third love to eat since they were born. 3rd loves to run and play a lot. Second acts like she's the mommy of everyone. Fourth (the one on the ground) was always sick and was getting skinny; turns out he had coryza and I treated him with garlic and apple cider vinegar in one of their water dishes. He seems to have gained some weight; looks more healthy now.
The first picture quail hardly drinks water by itself, I usually have to put its beak in there. It seems to have gotten coccidiosis today because of the soil. I think the fourth one had it too at one point, so I'm hoping the garlic-acv water works this time too.
Fourth one was always bald; has significant feather improvement in the past week. Third picture: he was always just furry and skinny, even though he ate a lot; seems to be growing feathers now.
Second picture was the first to get big and develop feathers; she loves eating . It seems like her wing feathers are getting bigger. She only had tiny feathers before.
First picture seemed to have feather development speed in between the 3rd and fourth.
I always check them and their stuff for mites. Haven't seen anything for a week or two. I do give them a shower on hot sunny days with dawn dish soap. Sometimes I spray garlic water on them and their cage. It seems to work. Just last week I got a spray for bugs which included fleas and ticks, so I sprayed their cage while they played outside.