Never said anything about the fragility. Just that breeding a silkied to a normal of the same breed, be it cochins, ducks or other, seems to be the best way to increase numbers in a very small genepool without directly breeding immediate family to each other.It does semm like the best way to increase numbers, but @dheltzel has said they are almost always more fragile compared to their normal relatives. @dheltzel no longer breeds for them, but still has them pop up from time to time. They also seem to be fragile no matter what you do. This has caused some speculation that the silkie mutation in Ameraucanas is connected to or is a lethal gene, kinda-of like how 2 frizzle genes creates a frazzle chicken with problems