90% of the time, it is the brake rotors. The Eclipse rotors are garbage. Even though her rotors are new, just her driving in the rain, making sudden quick stops, or braking from high speeds, will warp the rotors rather quickly. Still a possibility.

Her wheel bearings may be going bad also. Usually when someone replaces their rotors and still get a "vibrating" feeling, wheel bearings are usually the source of the problem.