Stock Tasks Widget - no longer shows groups

[iluvricky]

I was loving the stock Tasks widget on my S3 until recently, out of the blue, all my groups disappeared from the widget! Now, instead of showing my tasks by logical groups like "School" or "Grocery List", it's just one big category called "Undated." The groups still exist, however, and my tasks are nicely organized when I open the full calendar app. Any thoughts? Thanks in advance.