There is a world somewhere between reality and fiction. Although ignored by many, it is very real and so are those living in it. This forum is about the natural world. Here, wild animals will be heard and respected. The forum offers a glimpse into an unknown world as well as a room with a view on the present and the future. Anyone able to speak on behalf of those living in the emerald forest and the deep blue sea is invited to join.
It's actually normal behavior for sons to help their fathers against intruders if they are around and confident enough to join in ( obviously they won't join a clash they won't have the upper hand and it's a risky move because neither parent or son has a bond to make them confident enough that their partner will back them in a fight ), not different from when females charge at intruders, any member of a pride will help defend it ( and their territory ) given the chance and the odds.
It doesn't mean the sons will join the coalition ( though it can happen if the dominant male(s) feel they are too weak and threatened and see in their sons an opportunity to remain in power ), but obviously not the norm, they normally chase the sons aways given the time. In Notch's case he joined the sons coalition as nomads, after he was ousted and his sons chased away.