The big bang of Life Season 7 Episode 9:
Mrs. wolowitz invited everyone home for Thanksgiving dinner. Sheldon is not interested, he just wants Leonard's "Thanksgiving tradition" - though he's disgusted and critical of it. Leonard and Penny decided to accept the invitation, and Bernadette's father went (because his wife was out of town). Sheldon didn't want to go when they first met at apartment 4a. When people talked about Thanksgiving, Penny mentioned that he went to Las Vegas with Zack Johnson on Thanksgiving many years ago. They gambled and drank, and then a fake wedding was held in a fake Wedding Church. Penny is just for fun, but Leonard reminds her that the wedding churches are real! That means penny is officially married! Leonard asks penny to deal with it, and Amy looks for a reason for penny to abolish the marriage. They think "lack of understanding about weddings" is the best reason. Meanwhile, at wolowitz's house, Mrs. wolowitz was in poor health, so Raj volunteered to cook.