I say "eaglet bullying" in my video but the experts have a different take on it. The folks the The Southwestern Florida Eagle Cam say, "Survival of the fittest isn't a catch phrase in the Bald Eagle world, but necessary to continue their species.
Sibling rivalry varies between nests, depending quite a bit on the amount of food provided. Even when food is abundant, it is not uncommon to see some sibling competition – lessons learned which will help them cope when they are on their own.
In general, the first 20 days is when aggression is seen, but can be longer. As they get older, sibling rivalry lessens. There are no “bullies”, just eaglets trying to survive."