Like everyone else in their pastel world, the Abbotts are rabbits, and off season from their Easter egg business this artist family decorates their own car, a stunt diver's airplane, a bridge and whatever else might be handy. The appeal of their precise brush strokes and clean unshaded colors is probably greater than that of the story, which concerns young Orson's settling down to help his parents with their work. Nevertheless, Orson's efforts have individuality as he invents his own style of comic Easter eggs, and the whole Abbott ouevre neatly duplicates the intricate but transient perfection of those miniature painted eggs. Certainly a lighter touch than most seasonal offerings.