Express posts provides a widget to display either a subset of posts, the children of a page or its siblings.
The widget provides three modes.
Subset will list a given number of posts from your selected categories. Date, date format, and excerpt are all optional.
Children and siblings modes will list the immediate children or siblings of a page, respectively. You can include a placeholder in the widget title as a substitute for the parent page title. You can also choose to show or hide the widget on specific generations of pages, allowing extra flexibility on shared sidebars.
In common with all of my plugins, Express Posts strives to follow best practice in WordPress coding. If you spy a bug or see room for improvement, please let me know.