wp_list_pages: dealing with children and grandchildren

Hi people, so, here it is the situation:

I have in a div header where I have to display page menu,and
a second div where I have to display (if any) child nenu.
In addiction, I have to display the grandchild menu in a div inside a content page.

I have searched in support pages for code but all posts seems to be too old for me.
Can you help me with code?
Thanks a lot.
k