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The influence of different disturbance combinations and increasing sweep on laminar separation bubbles in a 3D-boundary layer is studied using direct numerical simulation (DNS) and spatial linear stability theory (LST). The focus is on 2D-disturbances, but for sweep angles larger than 10° to 15°, oblique waves trigger the strongest growth of background disturbances. LST is used to select the most amplified disturbances for each sweep angle, and its results agree with DNS within the linear domain. The study aims to determine effective disturbance combinations for swept laminar separation bubbles and to investigate the impact of sweep on stability and transition. A generic family of short leading-edge separation bubbles on a swept plate is calculated using DNS, and the underlying base flow is analyzed with LST. The numerical scheme is based on the incompressible Navier-Stokes equations, and different sweep angles are realized by varying the spanwise free-stream velocity. The flow is characterized by a Reynolds number based on the displacement thickness at the inflow. Disturbance calculations are performed by introducing periodic suction and blowing through the wall, and the structure of the disturbance cases is analyzed. The study finds that the specific choice of the primary disturbance has a noticeable impact on the transition process.