Ria's father wore the same, tattered shirt for 20 years. Then, she discovered the reason why.

For 20 years, Ria’s father wore the same shirt.

A green polo shirt, with a yellow collar.

Ria, a 24-year-old from Japan, couldn’t understand why her dad wouldn’t just buy something new.

“When that polo shirt gets a hole in it, he carefully sews it back together,” she told Buzzfeed News Japan.

“He wears it for any special occasion, be it a work study event or a trip out with the family.

“I wondered why he kept on wearing [it]… Why didn’t he just buy a new one?”. He never told her.

It wasn't until Ria was searching through her deceased grandfather's belongings that she found a photo that explained everything.

The photo was of her father and mother on their honeymoon, and her dad was wearing that same green and gold shirt he had worn all her life.

Ria's mother passed away from cancer 18 years ago when she was just 5 years-old, and in the honeymoon photos, she can be seen wearing a similar shirt in corresponding colours to her new husband.

"I never imagined that the polo shirt would contain such a special memory for him," Ria said of learning the meaning behind her dad's favourite shirt.

Ria shared her discovery on Twitter, and her story has since been re-tweeted over 82,000 times.

"I always thought he was so 'uncool' for continuously wearing the same old polo shirt," she said.

"But now I think that I have to look after memories too. I will never throw away anything important of my parents or grandparents."

Ria's story has resonated with people all over the world, reminding them that true love still well and truly exists.

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