Hi, We recently picked up a couple of "ducks" for the garden. Eight weeks in and not a quack to be heard. We were told they were 90% likely female, but now doubt has set in. They both still "peep" a bit, though one is deeper than the other. I've seen videos of really young ducklings quacking really loudly. These two are practically fully grown! Is it too late for them to develop a quack? Have we been mislead? Are we destined for supermarket chicken eggs for the foreseeable???