Hey everyone, I'm fairly new here and haven't long got into chickens. I'm a single father of 3 children and we got the chicken "fever". We started off with some Lavender Orpingtons and RIRs we found on CL back in the spring of this year. We bought them from a private breeder and everything had been going great for the last several months. Then one day I seen on CL someone else selling some Lavender Orpingtons, so being ignorant, I bought them (at night) and put them in the coop with the others as soon as we got home. I know that this is where my mistake was. The next morning the kids and I went out first thing to see our new chickens and to care for them. Much to our horror one of the new LO hens was laying over on her side and could barely move and the other had her feathers all ruffled and was staying in one corner. We quickly got them out of the pen with the others and I as quickly as humanely possible created a new "sick coop" to put them in. After trying several different antibiotics, spreading DE around (had it overnighted to me since I couldn't find it locally), and trying everything that I could find I ended up having to put down 3 out of the 5 new LOs we had gotten. By this point we were a week and a half into it. For a couple of days it seemed that everything was back to normal and we had defeated this disease. We had 3 baby chicks we had hatched out a couple of weeks prior to us getting the new LOs. One evening when checking on them I noticed that 2 of them were staying still and had their feathers puffed up. Then I noticed one of them had blood coming out in his poo. I quickly removed both of them and decided that it would be better to put them down than to risk any more birds getting sick. The next day the last of the 3 chicks was doing the same thing as the other 2 had. I had put it in a new box, bleached the feeder and waterer the night before, but apparently it was to late. I tried for a couple of days to get the last baby chick back to health but nothing seemed to help. It didn't seem to get any worse but it wasn't getting any better either. After a couple of days we woke up to it having died during the night. The kids and I were devestated but hopeful that things would finally be over. We had sanititzed every feeder, waterer, even our shoes, every day since finding the first two sick LOs. We had already been washing our hands before and after handling any of the chickens or caring for them (out of fear of E. Coli) and because it seemed like a good precautionary thing to do (which it is). For a couple of days after the last chick died we watched closely and didn't see any signs of any more sick birds other than a few of them had runny green poo. I figured it was from the antibiotics, and it may have been?, but then we noticed one of our RIR hens one morning was keeping one eye shut and it looked a little like her head was swollen. I thought that maybe she had accidently ate some poision ivy or had been stung by something. So, I used eye drops on her eyes and thought that she was okay. The next morning it was painfully obvious that her head was definitely swollen and that she was anything but okay. By this point I had made it a point to check on the chickens in the mornings before the kids got up. I couldn't stand to see them cry and see another sick bird. All said and done we lost all except for 2 of our chickens and I went ahead and put them down today because one of them had bubbles in it's eye and was already starting to act like it was sick. I've spent the last 9 hours cleaning the chickens coops, roosts, feeders, waterers, doors, wire, everything with bleach. I've bleach mopped the entire house, washed all the clothes, even the bed sheets and covers, disinfected our shoes again, cleaned all the door handles in the house with bleach water and then with the spray disinfectant. I'm going to repeat the process again this weekend and again next week. We have some eggs in the incubator but when we candled them it looks like we'll be lucky to get 3 or 4 out of them. They are due to hatch on the 1st of next month. I now know that you HAVE to isolate new chickens from your existing ones, have one pair of shoes just for taking care of chickens, and that by trying to save a few birds I believe we ended up loosing our whole flock (12 plus the 3 chicks). I really think that if we hadn't of tried for so long to hold on to the first ones that got sick and the last chick that we might would have stopped it from spreading to all the others. Even having them isolated on the opposite sides of the yard (the adult ones) from out "main coop" we still were not able to do enough to save our flock. I spent over $300 on antibiotics, cleaning supplies, new coop for sick birds, etc. The kids and I are devestated but hopefully when the 3 or 4 chicks hatch on the 1st we won't have the same problem again. I wish I had been smarter and hadn't of had to learn this lesson the hard way. I sincerely hope someone else can learn from my foolish mistake that just that one time ended up costing the kids and I all of our pretty birds, lots of tears, and hurt.