If you're attending a traditional white wedding, there's a golden rule isn't there? And everyone seems to know about it.
That rule is simple and really easy to stick to - you don't wear white.
That's why one groom's sister has confused people with her outfit choice as she turned up at her brother's wedding wearing a questionable outfit - a sparkly white gown.
On Reddit, someone posted: "Groom’s sister is told prior to wedding that her dress choice is inappropriate.
"Sister replies she will never speak to her brother again if he goes through with the wedding.
"She is uninvited from wedding, then shows up to wedding in this off-white cocktail dress."

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The sister is pictured in the centre of the picture, with her brother, the groom, to her right.
The other guests can be seen wearing darker colours, with one Redditor suggesting it may have been a Halloween themed wedding, causing the sister to stand out even more.
One wrote: "I thought the bride was the one in the middle, and that she was upset because the sister wore black. Then I finished reading…"
The original poster then continued in the comments: "I wasn’t part of this wedding but have seen so much drama about it unfold on Facebook.
"The bride is understandably very upset about what happened and posted something a few days ago about how she was disappointed that someone would act this way, but didn’t add any identifying info or name drop.
"Plot twist, the sister had separately posted a TikTok where she was claiming the bride was toxic and jealous, admitted to wedding crashing, mentioned how she had the last dance with the groom, and said she gives the marriage five years tops.
"The bride of course found out about this and there is endless Facebook drama about the TikTok, whether the dress was in fact 'white' (the sister claims it’s champagne…), etc.
"It’s been an absolute whirlwind."
Someone replied: "I'm so confused by mums/sisters/etc that do stuff like this."
"Can we just agree that for wedding purposes champagne = white?", another wrote.
Would you wear white to a wedding? Let us know in the comments.