MDX Parameter with Multiple Members Consolidated into Single Value

Today I was working on a report built on a cube and stumbled on to an interesting requirement by some of our client's end users (EU). EU wanted to be able to consolidate multiple, specific members into a single parameter value. For example, if EU selected the parameter item A, they should see all members in the report where the value is actually 1 A and 2 A. So by selecting a single parameter value, EU will have actually selected 2 parameter values and will see the associate members in the report.