How do I insert an extra line below the header?

How do I insert an extra space between header and line 1 in the back matter and have that display in the ebook? I have two pages that have it and two that don’t, and for the life of me I can’t find any difference between them. The text file for each starts with a blank line.

In the compiled ebook, the page headed Acknowledgements has the header, then an empty line, then the text starts. The page headed Also By has the header and then the text starts immediately on the next line.

Folder settings for Acknowledgements: Include in compile, compile as is
Text settings for Acknowledgements: Include in compile, compile as is

Folder settings for Also By: Include in compile, page break before compile
Text settings for Also By: Include in compile, compile as is

If I change the Also By folder settings to match the Acknowledgement folder settings, the header for Also By disappears but I still can’t get that extra line that actually appears in the file to display in the ebook.