Relative Severities 
Use
Apart from tagging a log controller to another log controller (see Relations Between Category and Location section), the amount of output can also be configured with respect to the relative(s). The evaluation of the message output not only depends on the log controller’s own severity level, but also on the relative severity of its relative(s), if any.
See also:
Set Up / Add Relative Severity
Output Resulting from Relative Severity
Alternative for User-Defined Severities