By comparison, Adelheid was the least skilled of the three but since she was the only pure-blooded daughter of the king, Adelheid was the only one who could become queen. When Adelheid first learned that Bridget was her sister, the future queen felt very guilty over the circumstances of her birth.
In comparison to the others, Adelheid was the least capable but as she was the only one with a royal bloodline, she was the only viable candidate for the throne. When Adelheid initially discovered that Bridget was her sister, the future queen felt deeply regretful about the circumstances of her own birth.