This mother-in-law's wedding fail turned out to be a surprisingly wholesome story

American romance novelist Amy Pennza recently set the internet ablaze when a photo of her mother-in-law arriving at her wedding wearing a bridal gown went viral.

"Top that one, Twitter," she wrote in the accompanying tweet.

Social media loves stories of wedding faux pas, disasters and histrionics, not least skid row catering, so the clamour to hear the backstory to the incident was huge.

After four days, Amy finally responded and had a surprisingly moving story to tell.

She began by describing the big day in detail.

She goes on to report "the wedding unfolded without bloodshed, or anyone being shoved into the champagne fountain" before launching into her explanation.

Here's the thing: My mother-in-law is extremely frugal. And I don't mean she just enjoys a good bargain. To understand her, you have to know where she comes from.

Amy goes on to say her new in-law grew up in "extreme poverty" and used to eat match heads (!) as a child.

She observes:

When you grow up with nothing, it stays with you. Forever, I think. No matter how much money you earn, there's always that little fear in the back of your mind that someone might take it all away.

The author recounts numerous examples of her mother-in-law's compulsive money-saving habits like saving uneaten salad in restaurants to take home and repainting her spectacle flames red with nail varnish rather than buy a new pair.

She's frugal. But she's also incredibly generous. When my twins were newborns, she drove across town every night, slept on the sofa, and did three feedings. For two babies. Every night for months.

A natural bargain-hunter, she spotted 'The Dress' on sale a discount in her size and couldn't resist making the investment, not stopping to consider the consequences of actually wearing it to the wedding and clashing with the bride.

Here's Amy's final assessment on an incident that proved to be a great deal more touching and understandable than the initial picture led us to believe:

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