Epitome Subtitle adds a subtitle field in the edit page of a regular post and static page. Note that a small coding is required to display the subtitle in the right location of your template. You provide to your theme the ability to display a title and a subtitle using functions that you call from your template.
Functions
the_subtitle() takes the current post or page ID and outputs the subtitle.get_the_subtitle($post_id) has one optional parameter (post or page ID) and returns the subtitle as a string.has_post_subtitle($post_id) has one optional parameter (post or page ID) and checks whether a subtitle exists.