Is it normal for ducklings hatched a day apart to be different in size

[quackerfactory]

One hatched a week ago, and the other one the very next day. The one born on the second day is about 1/3rd the size of the other duckling. Is this weird? He is always the first one to eat when I change out the food and water but he really has not grown very much in a week compared to his sibling.

 

[duckyfromoz]

I often have ducklings that grow at different rates. Sometimes it has to do with different parents- more so a different duck laying the egg. Even when I am hatching the same ducks egg they can still differ a little. Even though they are in the incubator at the same time- eggs can still develop a little differently too. Was there any size difference in the eggs at all? Or Different parents maybe??

 

[quackerfactory]

They came from the same nest and their eggs were the same size, the first egg pipped about 24 hours before the other one and they were both hatched completely 24 hours apart.

here is their size difference, that's the best I could get this morning before heading out to work. Basically the 2nd one still looks the same size he did 2 days after being born and the 1st one shot up like a weed and he is HUGE compared to him.

Apologies for my filthy brooder!

 

[quetsweyo]

I've hatched 3 batches of duck eggs and in my limited experience I've seen all the bigger ducklings to be drakes. I don't know if that is always the case or not, I am new to this. Quetsweyo