User blog:Flying Liberty/Heading 4 Subheadings: Bold or not bold?

On numerous Character Pages, I'd often see in the relationship sections that the characters the said character shares relationships with would be categorized; Friends, Family, etc. The category headings would be in Heading 3 format, which is bold by default and easy to distinguish from the text body. The character subheadings, on the other hand, are in Heading 4 format which isn't bold. In my point of view, this seems to make them blend in with the text body and so they aren't as straightforward to notice as Heading 3 Subheadings, even with the edit button beside them.

I've acted on this a few times by embolding the subheadings only for the edit to be undone. So is there anything wrong with having the Heading 4 Subheadings in bold rather than in typical font style? Though I think havint them in bold would help, I'm not sure about anyone else or if there are any regulations against it. Any words on this?