Petunia takes a stand

Vernon's reaction to having Harry dumped on the doorstep by *their kind* is predictable, and Petunia has a small epiphany over what might happen if Dudley develops magic when he is older the way Lily did. Suddenly her love for her sister is more important than her jealousy, and she takes steps to save Harry and Dudley by contacting the only person she knows in the wizarding world.