Ever watched that show “Bridezillas”? It comes with a parental warning thanks to rude language, some suggestive dialogue and even mild violence. The moral of the story: these are the brides you don’t want to be! Unfortunately, it’s harder than you think to avoid. The hardest part of a wedding is the event planning process—and you don’t have to have a serious mean streak to display at least a few bridezilla symptoms.

So what adds fuel to the fire? Surprisingly, not always the small things! It’s anything that wasn’t part of the plan when you started fantasizing about this fairy tale day as a little girl.

Exhibit A: your sister(s)-in-law. Love them, but they weren’t exactly on your radar 10 years ago. You and your closest girlfriends have been planning the line-up for your wedding parties since you were in high school—add your college BFF’s, and your roster is about full! Adding any more attendees might be bridal party overload.

THE ISSUE: What to do about your fiancé’s sisters?  Do you have to include them in the wedding party?

This one definitely puts some feelings on the line, but the answer is simple: sister-in-laws-to-be certainly don’t have to be in the wedding party. That being said, it does depend on the specific family situation. In some families, it’s completely expected…in others, it’s not—especially if you’re not close.

Gauge the situation, and choose tactfully. Being kind and conscientious throughout the process is imperative… it’s how you keep yourself off of shows like “Bridezilla” and are placed in more of the “glowing Kate Middleton-esque” bride category.

Other options: have his sisters do readings for the ceremony or stand up on your fiancé’s side if possible. Gender no longer defines whether you’re a bride or groom’s attendant! Nothing is required on your wedding day, but always consider your options.

Encountered even worse? Share your cringe-worthy stories—and how you were the picture of cool, calm and collected—on Facebook orTwitter!