A dysfunctional family gathering for a special occasion (be it a wedding or a funeral) has long served as a ripe dramatic backdrop for a reason. What better excuse to bring together a motley crew of characters who know exactly how best to push one another’s buttons and dredge up long-simmering resentments in the process?

Thomas co-wrote the script with her husband, journalist John Micklethwait, which includes a particularly poignant monologue for her character telling her daughters, essentially, to grow up and move on — a mature and worthy statement that might come a bit too late. “My Mother’s Wedding” feels only partially realized.