Reminder to self, don’t update the Sparkling theme to latest version (again) yet because somewhere between 1.7.7 to 1.8.1, a change in the backend caused the child theme’s previous Theme Option settings to not be used. Instead, the parent theme’s settings is being used.
The only way to fix is to downgrade the theme back to a version where the child theme settings are still used, note down what those settings are, then upgrade the parent theme, then implement those settings again. Urgh, so troublesome.
Source, although it’s for a different theme by the same theme developer, it describes the exact same problem so I’m guessing the mentioned framework is being used for Sparkling as well.