Hi - appreciate any advice - we have a vet visit scheduled for Monday which is the soonest I could get an appointment. 10 week old Pekin that is just off - she (?) can't walk straight - she holds her feathers kind of funny and she tumbles over to one side or on her back quite a bit while trying to walk. We have had all 4 of my ducklings on brewer's yeast since week one and I even bought her a B-12 liquid supplement this week because I thought maybe it was niacin. But I'm starting to think it's a neurological issue - she also is much smaller than the male and at 10 weeks she is not "quacking" - just making a raspy drake noise but no curly feather. Any ideas? We are making sure she is getting plenty of water exercise - she is not showing evidence of foot or leg problems - just tumbles over on her back or side.