Please help - 3 day old duckling not thriving like her sister

[dehave]

I got 3 baby ducklings on Saturday. 2 were just a few hours old and 1 was 2 days. Dandelion has looked weaker than the other 2 since she was hatched. She is making progress every day, but is still behind her sister that she hatched with. You know how when they are first hatched when they fall asleep their heads slump down to the ground, but when they are a little older and they sleep their heads resting upright on their bodies? (does that make sense?) Starting yesterday her sisters head rests upright while sleeping but she still just lets her head fall where is may. Her eyes also bulge out a little. It's like the her face hasn't filled out completely. She also falls asleep constantly. She can run around and she eats and drinks well, but then falls asleep about twice as often as sister. Could she just be sleeping alot to catch up? Is it okay for them to progress at different rates? Also, her bill seems paler than her sisters. And her sister seems a little bigger than her today. We named her Dandelion after a duckling that we tried to rescue that died right when we got her home. I don't know what my daughter will do if Dandelion 2 dies. Thanks.

Also, She is breathing heavier and there is a tiny click sound with each breath!

 

[Kelpie]

On the breathing issue, what food are you giving her? I learned the hard way not to give ducks food that is old or has been damp or they get aspergillosis from the mold. If your feed is questionable stop feeding it to them immediately and clean the place. It could also be from food from wherever you bought her. I have never been able to save a duckling with this but you may read up on it and try fungicides.

 

[dehave]

Thank you for responding. I panicked yesterday because she looked so weak, so I took her to the vet. Overkill, probably, but worked for my peace of mind. Anyhow, she gave her some baby parrot formula after reading up on it on one of her vet resources. She gave her a full exam and says that she is just a runt. They also flushed her nostrils with a teeny tiny dropper. She said the poly vi sol with iron is fine for short term. By last night she had already perked up. She is standing more and opening her eyes wider. By this morning she had lost her egg tooth and her beak color is improved. She is trying to run around with every one else. She still falls asleep more and is breathing a little heavy, but she is much improved. I am soooo happy. BTW, yesterday she was about 7 grams less than her sister who hatched at the same time.

I'm having a good day, all the birdies are doing well and my 5 week old foster kittens eye infection has cleared up, so we are happy!

Thanks!