The Biological Family's Tension At their Adopted Child
The "Elephant In the Room" is the biological family's tension and unspoken problem of the adoptive family's dysfunctional dynamics and lacking cohesion.
The desperate need to blame, that is required in the identification of the family scapegoat adopted child.
In the Nuclear family's ability to point the finger at the problem is business as usual, as this adoptive family acknowledges the "problem" among them- and they all silently agree that it all stems from the adopted alien child's presence.
That no family problems existed before the arrival and forced entry of the adopted child. The family's biological offspring resent the adopted child's presence and are offended by this alien outsider's presence to the cohesive family unit. The growing hatred of the biological children eventually becomes detrimental to the psychological health of the outsider that exists continually in survival mode, never letting their guard down of the adopted child's reality of the biological sibling's hatred of them.