It's a sacred tradition that a bride-to-be should always keep her wedding dress secret from her future husband.
But one bridesmaid committed the ultimate wedding faux pas.
She not only posted an image of the bride-to-be's dress but tagged her future husband in the post, too.
The horrified bride-to-be left a message on Mumsnet, The Sun reports, asking for advice.
She wrote: "I know I probably am but just wanted to hear others opinions on whether they would be sad about it or if I just need to get a grip!
"Getting married soon and after trying on a lot of different dresses I finally found the one, something I never thought I would due to being very body conscious and anxious."
"Went back for final fitting at the weekend and took one of my bridesmaids as she wanted to see," she continued.
After finishing the appointment and getting home I saw that she had posted a photo of me in the dress on Facebook.
"After finishing the appointment and getting home I saw that she had posted a photo of me in the dress on Facebook (during the appointment so it had already been on an hour or two when I saw it)."
The mortified bride-to-be went onto explain that the bridesmaid tagged her fiancé in the picture, saying that she bet he couldn't wait until he marries her.
The bride-to-be's dad also saw the post, ruining the surprise for them both.
She said that the dress had been paid for in installments, and there was no time to replace it or get another.
Mumsnet readers were quick to share their support and offer up some drastic advice.
"I'm sorry but she should not be your friend or bridesmaid," one said.
Another wrote: "I can't believe someone would do that."
One more said: "Your dress is your secret until the day of the wedding."
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