Where would you like to add that list of child pages?
If the answer is to a page, than repeater web part, or any other from Listing and Viewers section, will do this for you, unless I'm missing what your goal is.
In the repeater web part you can specify the path to show pages within (either static or macro), and transformation, along with other settings. In your transformation you can get a link with either
GetDocumentUrl methods. Find more methods here.
This will result in a page listing, which will change anytime new item has been created under the specified path.