cameraviewport problem

i have a main camera and a mini view camera, they both work fine using the sample code below

cam1 = createcamera()
cameraviewport cam1,0,0,GraphicsWidth(),GraphicsHeight()

cam2 = createcamera()
cameraviewport cam1,0,0,GraphicsWidth()/3,GraphicsHeight()/3

now the problem comes when i parent my cam2 to another entity ie

cam2 = createcamera(parententity)
cameraviewport cam1,0,0,GraphicsWidth()/3,GraphicsHeight()/3

or entityparent cam2,parententity

the viewport stops showing up.
am i doing something wrong ?



EDIT: typo fixed :p