Duckling hatching two days early

[jenM4]

I had three eggs in my incubator all set to hatch different days. (The 15, 18, and 20) I noticed the other day that the one set to hatch the 20th already moved to the air cell. The one for the 18th pipped externally a day early. The one from the 15th had to be helped yesterday hatch because she was shrink wrapped. I'm not sure if she broke the egg or if the duckling inside did but I noticed she pipped. It's two days early. The temp hasn't been messed with and the humidity is the same also. I'm not sure what to do what are the chances of her making it if she hatches before the 20th? I moved the duckling that already hatched to the brooder. The first duckling seems to have a niacin deficiency I think. She's jumping and seems strong and healthy but she keeps falling over. I'm not sure if it's something wrong with her legs or a deficiency. I've already provided something to help with it though. She's doing good after I gave her something she seems to be walking better but still wobbly. I've got older ducks and chickens but never hatched anything myself till now. I'm not sure what to do if she hatches early.

 

[Yardmom]

How are your ducklings doing?