borderless window

hi

   I m creating a application where in my mainwindow i have  a
button ,when clicked on the button it should display a child window
just below the location of button,

 i drag and drop a window to the doc and give a name "picture", in my
IBaction
 then i   add child window "picture" to Main window "window1"

[  window1 addChildWindow:picture ordered:NSWindowAbove]

It working ,but its not displaying just under the button location,
how can i display the child window just below the location of button;



Thanks