A vehicle door includes a door inner and a trim panel fixed to the door inner. An energy absorber having a vehicle-rearward end and a vehicle-forward end is disposed between the door inner and the trim panel and elongated in a vehicle-forward direction from the vehicle-rearward end to the vehicle-forward end. The energy absorber includes a first energy-absorbing component defining a cavity facing the trim panel, and a second energy-absorbing component disposed in the cavity. The energy absorber has a stiffness that decreases in the vehicle-forward direction.