Noisy Friarbirds

I really enjoy seeing Rainbow Lorikeets around my yard. However, a number of my blogging colleagues have said that Lorikeets are very aggressive birds. Over the last month or so there have been fewer and fewer Lorikeets in my Grevillea tree. They have been driven off by extremely aggressive Noisy Friarbirds! The Friarbirds sit on the top branches and seem to warn any other birds that the tree is theirs!
I don't know if this is a normal "pecking order". Yesterday I found part of the reason! I heard small bird noises down in that area of the garden and when I looked I found this nest. I first discovered it because of the piece of paperbark that was not properly fitted around the nest and hangs down below it. When I went closer to look a Noisy Friarbird flew off. I can't see into the nest as it has been carefully constructed so that it is behind some leaves. I climbed up on a step ladder - far enough away that I would not be too much of a disturbance - and I can see baby beaks waving around just above the rim of the nest. To see more I will have to wait until the young birds get big enough to move out of the nest.