In March, our 4yo hen Jane suddenly stopped walking. She just sat. After about two days of this I took her to the vet. He said she had an abdominal tumor and to take her home and make her comfortable. She died two days later. Now, our 3yo Helen is doing the same thing. Helen is an Australorpe, by the way. She is just sitting in the roost box, on the hay. She's not perching, not leaving the box. There are no eggs, so it's not as if she's gone broody. She is not eating or drinking. Our other two hens (Lucy, a RIR, and Ethyl, a white Plymouth Rock), are also three. They have all stopped laying. It's hot here, but that's not unusual. They are eating well, and drinking; roaming the yard during the day; seem to be doing fine other than no one is laying. My flock consists of these three birds plus 3 pullets and a duckling that are housed separately. Any help you can offer?