The Honker and Alarm Caller:
I know it's not white feet. I think it might be the middle child, but not 100% sure. Knowing what position they were in during their nap, I used the archives to figure out which one it was, and tried to get a picture that would show feet.
Based on facial feathers I changed my mind on who I think is eldest. I think Blue Foot is actually the middle child, so I think honker is the eldest.
But then again, I could be wrong.