is there a way to sort only on second level headlines in org mode?
i am outlining a novel with top level headline being the chapter number and the second level headline being the timeline of the events in that chapter starting with a number = YYYYMMDD. the top level headline starts with a number representing the chapter. i have made the top level headline chapters high numbers in a hundreds sequence for ease of interpolating new chapters later, e.g., adding a chapter between 200 and the next chapter, 300, only requires adding at the end of the outline the new chapter with a top level headline of 250 and then resorting numerically. the second level headline is a different (chronological) number since chapter 300 may be a flashback occurring earlier in time than, say, chapter 100.
(see examples below)
if i could have two different ways of sorting (by chapter and by timeline), i could visualize the narrative more easily as i progress.
i have done some searching online for a solution and have considered tags and properties and functions but although i have been using emacs for about 5 years now (mainly as a text editor with .txt and .org and .markdown) formats, i am a writer with no programming or coding skills.
example of sorting by chapters (top level headline):
* 100 stranger comes to town ** 20190911 * 200 stranger meets chanteuse ** 20190925 * 300 stranger tells chanteuse a childhood story ** 19900525
example of sorting by timeline (second level headline):
* 300 stranger tells chanteuse a childhood story ** 19900525 * 100 stranger comes to town ** 20190911 * 200 stranger meets chanteuse ** 20190925
thanks for any help. i am not committed to org mode. any help will be appreciated. i could do this via a spreadsheet or a database manager, i realize, and have done so in the past, but would like to stay with emacs, which i use as aquamacs on an apple laptop.