Grandmother realises she's been wearing the wrong flag to celebrate Fourth of July for 25 years

Despite the confusion, she will continue to wear the shirt on the Fourth of July

Grandmum confuses Panama flag for American flag on Independence Day shirt (Stock)

An American grandmother has discovered that her favourite patriotic USA shirt wasn’t representing the country she thought - after her grandson watched the World Cup.

Shirley Cheesman, 88, has worn the same stars-and-stripes-decorated shirt every Fourth of July for nearly 25 years to celebrate America’s Independence Day.

But after watching this year’s World Cup, her grandson Dale, from Houston, Texas realised that the shirt actually resembles the Panama flag.

Although the two flags bear the same red, white and blue colours, and stars, the Panama flag is distinctly separated into four squares.

Dale shared his realisation on Twitter, where he humorously referred to his grandmother’s dedication as treason.

He wrote: “My grandma has worn the same shirt with red, white, blue, and stars to celebrate the Fourth of July for more than 25 years. Every year, she wears the exact same shirt.

“Thanks to the #WorldCup we finally noticed it’s the Panama Flag. Over 25 years of treason.”

The tweet has since gone viral and received more than 55,000 likes.

In addition to amused reactions, the family has received invitations to visit Panama by proud Panamanians.

Despite the mishap, Dale told the BBC that his grandma will continue to wear the shirt - as it is a tradition.

“If anything I might buy the whole family Panama shirts to wear on July Fourth,” he said.

This year was Panama’s first year playing in the World Cup - they were beaten 6-1 by England in the group stages.