Don t ever try to have them stay in one place for too long. Trinkets of all sorts tending to the unusual. Silver preferred over Gold. Can be seen wearing numerous rings and bangles to accent their lovely hands and arms. Photos would also apply here.
Food is a great gift as well as kitchen appliances or cookware.
A great meal cooked especially for them always works. Silver and shell colors like abalone are favorites of theirs. Soft cashmere sweaters as well as silvery shimmery moon clothes for those nights dear Cancer wants to shine. Trips to the ocean or aquarium will calm these Moon children. Telescopes to view their planet as well as visits to a Planetarium.