Wedding guests shocked by mother-in-law's white bridal dress

It’s a cardinal rule at any wedding really - don’t upstage the bride.

Generally this means that guests, including family members, should steer clear of wearing anything white or off-white, and should definitely not wear anything remotely resembling a bridal gown.

But it seems this mother missed that memo, as she rocked up in exactly that to her son’s wedding.

A ‘distant family member’ shared a photo from the nuptials to a wedding shaming group on Facebook, and it has now gone viral.

“Groom’s mom just had to wear a bridal dress too,” the person captioned the image.

The bride holding the bouquet in the centre of the photo wore a lace wedding dress in a mermaid cut.

Her new mother-in-law also decided to wear a white lace floor-length dress. The colour is slightly different, and the cut is more straight, but as most people pointed out, it definitely just looks like another wedding dress.

“I swear if my future MIL does this I'm losing my s***,” one person wrote. “I will be asking her first hand what she plans on wearing.”

“I'd have refused to have a photo with her, to be honest,” another said, outraged.

But some people couldn’t see the fuss with the picture, even commenting they thought the mother’s dress was nicer.

“I honestly don’t see the problem. It’s not like people don’t know who the bride is. Wouldn’t bother me what so ever,” one person wrote.

“#hatetosaythis but MIL’s dress is better / more elegant than the bride’s weird lacy mermaid concoction,” was another response.

Got a story tip? Send it to lifestyle.tips@verizonmedia.com

Want more lifestyle and celebrity news? Follow Yahoo Lifestyle on Facebook,Twitter and Instagram.

Or sign up to our daily newsletter here.