In Drupal 8, I have a hierarchical taxonomy vocabulary called "Living Things" containing these terms:
Animals --Fishes ----Blennies ------Yellow Blenny ------Green Blenny ----Gobies ------Blue Goby ------Red Goby
I have created a custom content type called "Taxon Page" which includes a single reference to the "Living Things" vocabulary.
Using the "Taxon Page" content type I have created a page for each of the terms in the "Living Things" vocabulary. So for example, my "Yellow Blenny Facts" content page contains a reference to the "Yellow Blenny" taxonomy term.
On those "Taxon Page" content pages, how can I display only content that references that taxonomy term's immediate children (if there are any)? For example, the "Fishes Facts" content page should display data from the "Blennies Facts" and "Gobies Facts" content (not just a link to those taxonomy terms), but not their children.
I have tried to achieve this by creating a view for "Content type (= Taxon Page)" and adding a "contextual filter: Content: Has taxonomy term ID (with depth)" (depth of 1) but it did not work.
Note that this question is related but different, as it only refers to taxonomy terms, not content referencing those taxonomy terms.