Prefab variant pointing to base prefab component in scripts

I have a base prefab with a script with serializefield pointing to component in one of the base prefab children. It is set by draggin and dropping in inspector. But when I point the right component in my base prefab all prefab variants are pointing to the same component in base not their own copy. Is it how it supposed to be? Can it be altered or do I have to through every prefab variant and drag and drop every component?