Hiding a window instead of "destroying" it

[Ignacio <inodal teleline es>]

Hi, I have an application with a main window and several child windows. 
I want to create all this child windows when the program is executed,
but only show/hide them when a particular button is pressed. So, the
child windows should only be destroyed if the main window is destroyed.

I don't want to let this child windows to be destroyed not even using
the "X" in their title-bar. It would be nice if I could connect this
particular signal to gtk_widget_hide. Is this possible?

Thanks,
	Ignacio