Well, bad news and good news. A lot has happened in the past week.
I've been keeping the two sick ones in a laundry basket in the house. Giving vitamins, feeding lots of good food and keeping an eye on them. Unfortunately Tilda (my little BA that's been sick for so long) took a turn for the worse. It got to the point where she couldn't walk or stand at all - just rolled around, flapped her wings and cried. She developed a pretty bad neck tremor. The only way she could eat or drink was if I held her and stabilized her neck, and even then she seemed to really struggle. Although I did this every couple hours and she seemed hungry and always tried to eat, she seemed to start losing weight by the hour. We decided to put her down.
At this point I really didn't think she was going to get better, and I couldn't justify letting her go on in the condition she was in.
Priscilla (my EE that came down with this about 2 weeks ago) seems to be doing better though. Yesterday when I came home from work I cleaned out her basket and gave her fresh food and water. She stood up and started eating like there was no tomorrow. Today I took her outside for a while to get some sunshine and fresh air, and she started walking.
I took her out again tonight and she managed to walk around quite a bit and even fly a little. Then she preened, ate some grass, and curled up in my lap. She does limp a little, and she wobbled once or twice but didn't fall over. This is such a huge improvement - last week she wouldn't stand up at all. I'm really hoping that she'll recover and go on to lead a fairly normal life.
Does anyone have any advice on how long I should wait before letting her go back out with the others? Also, if she does recover, will she need any special care? Is there anything I can do to minimize the chances of a relapse?
Thanks again for all the advice and support everyone.