Gathering a couple's entire family, childhood and work friends, and overall closest people all together for one party with dancing, flowing champagne, sentimental speeches and sometimes an open floor with a microphone can be pretty dangerous.
That aunt who is usually quiet and classy can turn into someone who is desperate to drop some raunchy wedding night advice on you after just a few sips of chardonnay. That uncle who you've never spoken to is suddenly pulling the groom aside to tell him "how to cheat without really cheating," and in general, it's probably best to take all wedding day advice with some extra grains of specialty cocktail margarita salt. Most of the time, it's fair to say that people in the unhappiest marriages are the ones who think they know everything about how to have a successful marriage. Trust your instincts and your partner, not your cousin Maggie who is making out with the DJ in the bathroom.