Do you have "hide from lists and menus" checked on the board that does not show up? (click on "edit properties" to check this) That will cause it not to display in the list of boards.
Thank you for the response! The boards are all on the same level. Just to be sure, I added the /nested parameter, but I am still only returned 2 boards.
Here's what it looks like in the community structure:
Both API calls (with and without the "nested" parameter) return the first and third boards, but not the middle one.
Check the permissions set on each of the boards vs. the permissions allowed to the user you are making the REST API call as (or if you are making the call without the restapi.session_key parameter you are making the call as an anonymous user and have the default permissions set on the board) -- it's possible that one of boards has permissions set that don't allow the caller to see the board and that is why it's not being returned in the results.
Do you have "hide from lists and menus" checked on the board that does not show up? (click on "edit properties" to check this) That will cause it not to display in the list of boards.
