How do I make the category sidebar widget (stock) display the total # of posts including those in subcategories?

Thanks for taking a look at this for me.

You can see the current behavior at http://dev.citylightphilly.com/blog/ — Here is my specific problem.

We are using a category structure like this:

Events []
  Meals and Mission []
  Service []

Our problem is that our users are categorizing events like this:

Events []
  Meals and Mission [x]
  Service []

This results in the sidebar widget not reflecting the total number of events in the post count. For instance – we have 8 posts in “Meals and Mission” and 2 that are simply in the “Events” category. We’d like the sidebar to reflect the total post count like this

Events (10)
  Meals and Mission (8)

However, the post count looks like this:

Events (2)
  Meals and Mission (8)

EDIT: moved the quick fix to an ‘answer’ below.

What I’d prefer to do is tweak the widget to reflect the total number of posts in that category, including all its child categories. Is this possible? I’m using the stock “categories” widget.

Thanks!