Viral Twitter thread shows mother-in-law show up to wedding in wedding gown

You know the unspoken rule, never wear white to a wedding, unless you're the bride, of course.

So it goes without saying that wearing a bridal gown as a guest is a bad move.

A photo shows a bride, Amy Pennza, standing next to her mother-in-law -- who is also in a wedding dress.

Pennza tweeted, "My mother-in-law wore a wedding dress to my wedding. So, yeah, top that one, Twitter."

Well, this went wildly viral because why wouldn't it?

Her hair is even in an updo.

Pennza says she didn't know what her mother-in-law planned to wear.

She didn't think to ask.

She sees her at the church and says, "You could be the bride."

Her mother-in-law grew up in extreme poverty and Pennza knows she wasn't being cruel.

She just found an incredible bargain and ran with it.

Fortunately, there wasn't any bloodshed at the wedding or "anyone being shoved into the champagne fountain" and while the mother-in-law feels terrible about it now, this moment made the wedding unforgettable.