Cyn, in your experience do you think this problem is most likely to manifest itself within the first couple of years of life or can it occur at any time? I have 8 hens that are 2 1/2 years old and I do have one that has classic internal layer symptoms that started about 6 months ago. I'm wondering what the likelyhood is for more to develope the same problem, or if it's unlikley once they are a bit older and doing well.