Twins

Twins are a them that appears in King's Quest beginning with the birth of Alexander and Rosella.

But there are other ideas that are twinned together as well.

Behind the scenes
The idea of Alexander and Rosella being twins is likely taken from the story of Rapunzel in which she gave birth to twins in the desert while her Prince Charming was lost.

The Zodiac symbol for Gemini the twins appears in KQ8.