How to add the same slider to different child pages that does not refresh

Hi I am trying to find out a solution for the following problem:
I have a series of child page (which I know the parent page id) -> the navigation between these child pages is made via a submenu in the sidebar. I would like to add on top of main content + sidebar on each child page a fullwidth slider. I can do it by using the Layout Bluilder on each page, but in doing so when I switch from one child page to the other (in the frontend), the image, together with the whole page, is obviously refreshed.
Since the image is the same on all the child pages, is there a way to add this picture as a header element (hence fixed and not refreshing) via the functions.php hooks? In a way that when the function detects the child pages of a certain id parent page it adds the fullwidth slider just below the logo/main menu area.

Thank you very much