  Certain quasi-exactly solvable systems exhibit an energy reflection property
that relates the energy levels of a potential or of a pair of potentials. We
investigate two sister potentials and show the existence of this energy
reflection relationship between the two potentials. We establish a relationship
between the lowest energy edge in the first potential using the weak coupling
expansion and the highest energy level in the sister potential using a WKB
approximation carried out to higher order.
