Hi I recently acquired two gorgeous ducklings. I was told the slightly bigger one is male and the other is female. Certainly by the sounds they are making this seems to be the case. The smaller one is much more vocal with very distinct "peeps" whereas the other is very quiet. However the "male" is developing faster...he is already getting adult feathers on his chest and sides...and his wings are much bigger than the "female". The "female" has no adult plumage yet. But the "male" is still only a little bigger than the female. So do males tend to develop quicker? Is it normal for one sibling to be develop earlier? Or could they not be siblings after all? Thanks in advance.