I purchased four ducklings in June. I was told the drake was a Khaki Campbell and the ducks were either Rouen, Blue Swedish or Welsh Harlequin. I know two are definitely Rouen X's, but not sure of their sex. They are approximately 10 weeks old and are going through molt. Do I need to be patient and wait to see what adult feathers emerge? These two also don't make much noise...kind of half-hearted attempts at quacking but doing it more frequently. One definitely "whispers"--pretty sure it is a drake. The other two are definite quacky and I'm pretty confident they are indeed ducks.