The Gemini Flag is predominantly yellow, since yellow is the middle color in between red and blue, of the rainbow. Gemini's are associated the ambiguous middle.
Does a Siamese Twin with two heads have two souls in one body, or one soul expressed though two bodies, or two souls with two bodies merging? If this Siamese Twin is has one body then if she has a child does the child have one mother or two?Ambiguous indeed.
An interesting fact is that several of the US Gemini Astronauts were coincidentally also born under Gemini - David S. Scott, James McDivitt, and Pete Conrad.