While hen parties are all about having a good time, there's an unwritten rule that the bridal party should never outshine the bride.
One woman was fuming, therefore, when her sister-in-law rocked up to the celebrations in a "bridal-looking" dress and glitzy tiara.
Putting a downer on one of her final nights as an unmarried woman, the bride-to-be claimed that she refused to include the guest in any of the photos.
Taking to popular forum site Reddit, the woman has questioned whether she was unreasonable to be so cruel as the ordeal has caused a series of arguments amongst the family.
She explained: "I'm getting married and my brother 'John' asked me to include his girlfriend 'Sarah' as a bridesmaid as a way to get her involved with our family since he wants to propose soon. I wasn't happy (she's quite snobbish, almost in a comically villainous way). But I love John and it mattered a lot to him, so I agreed.
"On the final night of my bachelorette party, we decided to have one big meal that was really pricey and fancy that we all saved up for. Guys, when Sarah showed up, I was FLOORED. She came in a white sparkly sequin number with a tulle skirt and a tiara.
"When we were planning the trip, my maid-of-honour made it abundantly clear that everyone was supposed to wear pink so we could get a really cute photo together at the restaurant.
"I'm not even kidding, her outfit was so bridal-looking that the waitress actually asked if we were having a joint bachelorette party."
After admitting that she was "so upset" about the situation, the bride proceeded to "absolutely refuse" including her sister-in-law in the photographs.
She went on: "She said it wasn't her fault because she 'didn't get the memo', but I told her it was common sense to not wear a bridal-looking dress to a bachelorette party if you're not the bride! Plus, she was in the group chat and even made comments about another girl's outfit when we were talking about what we wanted to wear, so I know she knew!
"All of my friends were on my side and they made sure she didn't end up in the photos. When we got home, she pitched a fit to my brother saying that we bullied her at my party and deliberately left her out. She was also p***** because a lot of family and friends noticed she wasn't in the photos and I wasn't afraid to tell them exactly why.
"My brother's really upset though because she's been crying and whining about it nonstop since. Apparently, they're both so mad that they're going to skip Father's Day brunch, so the whole thing is blowing up even more."
She added: "I'm starting to feel bad because my mom told me that my brother and Sarah were fighting a lot now, so I'm not sure if I'm being the a**hole here. My brother called me a bridezilla, but I really feel like Sarah was trying to ruin my night."
Since sharing the post online, the woman's thread has raked in over 1,900 comments to date
One person wrote: "Not the a**hole! A TIARA and a TULLE SKIRT? All in white? Someone was clearly jealous of the attention you were getting. If the drama continues, I would reduce the size of the bridal party by one."
Meanwhile, someone else said: "I wouldn't let her attend the wedding at all."
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