Grandmageddon

The wrath of the family matriarch that is generally triggered by doing something tremendously displeasing to Gma. This wrath can range from cold stares and cutting comments around the Thanksgiving table, to extended guilt trips, to having family lakeside cabin privileges revoked, and even to having her rewrite you out of her will.
Grandmageddon should be avoided or delayed at all costs, because unlike other people, she is much more likely to carry her grudge to the grave- mainly because the crazy old bitch is not to far from it.