Preventing groups from being hidden, but still rollup? SSRS 2005

I have a report that looks something like this in SSRS 2005 Layout designer:

                                            Amount
ParentLineNumber       ChildLineNumber      =Last(Fields!Amount.Value)

This is bascially a balance sheet, and some rows(parent rows) are subottals of the other rows. The subtotals always appear, but the users want to be able to had the other detail rows whenever they are a part of a subtotal. (Note that I don't calculate these subtotals, they are rows in the database query because they were entered by an accountant, and it is important I use their subtotals and not recalulate, hence the reason I don't use sum()). So the below is what the report looks like so far where row 4 and 7 are subtotals:

       4  1    $100
       4  2    $400
       4  3    $150
   -   4  4    $650
       7  5    $500
       7  6    $400
   -   7  7    $900

So with one group toggled:

   +   4  4    $650
       7  5    $500
       7  6    $400
   -   7  7    $900

Other group toggled:

   +   4  4    $650
   +   7  7    $900

Etc.

       4  1    $100
       4  2    $400
       4  3    $150
   -   4  4    $650
   +   7  7    $900

The issue I'm having now is I have added the description for the line items. QUESTION: How do get the descriptions to not disapear, and use my last function the same way it works for values? Like this:

                        April   June   
   +   4  4  *Fruits*   $650    $750   
       7  5  Carrots    $500    $650   
       7  6  Celery     $400    $345
   -   7  7  Vegetables $900    $795

What I've accomplished on my own, problem here is it's missing descriptions for rolled up items :(

                        April   June   
   +   4                $650    $750   
       7  5  Carrots    $500    $650   
       7  6  Celery     $400    $345
   -   7  7  Vegetables $900    $795

Problem: When the group is rolled up the description text disappears. In this example it is showing the value for line 4, the parent subtotal, but the decription for line 4 is missing.

I tried changing the expression of the groups as well to use the Last function, but they still get hidden. This is what may layout looks like now:

                                                                                       Amount
ParentLineNumber   =Last(...ChildLineNumber.Value)   =Last(...LineDescription.Value)   =Last(Fields!Amount.Value)

The second group is set to be visible based on the ParentLineNumber group, which obviously is why those columns get hidden. So how do I keep the +/- rollup option on the ParenLineNumber, and also always show the LineDescription?

I am really new to SSRS and have made alot of effort playing with different things trying to work this out. Thanks.

EDIT: The other thing I considered was setting the group value like so:

IIF(Is Collapses show ParentLineNumber&ParentDescription, else show ChildLineNumber&ChildDescription)

By doing this in the first column, then when it is collapsed then it will still show the description for the parent. But I couldn't figure out how to accomplish this because I still need the first gorup to just be something that is the same for all children so that I can collapse them, which of course hides the subgro开发者_运维知识库ups :(