Example:

T1 is the primary block task and T2 is a base task of T2 and T2 has Concurrent Exe. Specific relationship with T3 (related task). T1, T2 and T3 are packaged to P1.

If the check box 'Show Related Tasks' is checked, the T1, T2 and T3 tasks from the package P1 will be retrieved in the report. If the check box 'Show Related Tasks' is not selected, only the T1 task from the package P1 will be displayed in the report.