Does the caged bird sing?

Although it is tempting for the Golden Child and the Scapegoat to be in conflict, If they ever become aware of the situation they are in it is possible to develop pity and compassion for the other.
After all the roles are often interchanged between them according to the whims of the narcissist, so they seem to ether develop an empathy, or extreme antipathy for each other.

My sister I feel great pity for. She did, to quite an extreme degree, what a lot of children of Narcissists do. She destroyed her own life in order to protect herself. At least that's how it seemed to me. She courted and achieved failure in the things that my parents took pride in her being able to publicly achieve. Education, career, social success.
She evaded becoming competent in anything better than the basics of self care.
She made decisions, and failed to make decisions, which slowly closed down her life, her potential and her communication with the outside world.
It is with a great deal of sadness that I was witness to her doing this without being able to stop her.

It was not unlike watching a canary build a cage to keep themselves safe from a cat. Then happily close the door, believing themself safe, and yet they don't feel safe. Because now they and the cat are constant and close companions.
The canary is always in the presence of the cat. So it continues to build diligently, adding to its cage - making it stronger from the inside, all the time reducing the space it has to live in, and still never feeling safe.

Yet all the while - the window was open, but the fear of the outside world was worse than the freedom it offered. That, I think, is the burden of the golden child.

They are often not safe people to try to maintain relationships with. As they (mine certainly) would sacrifice anything to gain a greater feeling of distance and safety.  Including me.