Long-distance relationships can be gruelling. Often couples will exchange love notes to keep the romance and spice alive.

But for one daring couple, the raunchy letters they wrote to each other in their early courting phase has come back to haunt them in 2018.

The man's wife decided to pull their old love letters out to reminisce on their X-rated antics before putting them away in what she thought was a safe place.

But just three weeks later the couple was left mortified when they realised their three-year-old daughter got her hands on the letters and placed them in neighbours' letterboxes.

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The three-year-old's mum was left red-faced when the neighbour popped around the return the raunchy love letters.

The husband, who wishes to remain anonymous, told Mirror Online he's received from funny looks since the embarrassing incident.

"My daughter found them and went on her Postman Pat delivery.

"A neighbour returned some of them to my wife. Oh happy days.

"I think the neighbours read them because when I arrived home I got some funny looks."

It's not the first time a family has been left blushing over old love letters.

Just weeks ago a group of sisters who thought they uncovered their parents' romantic correspondence were left horrified after reading what was inside.

While their father was working away in London in the 1960s, he sent letters to his wife back in Scotland to reassure their love for one another.

Those love letters were stored away for more than 50 years, until the couple's daughters stumbled across them.

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Twitter user Morven from Scotland explained how she and her sisters decided to sit down and read the letters together as a way of remembering their mum.

Unfortunately, they weren't prepared for what was inside.

"After my Mum died we found letters, tied in a bow from my Dad from when he worked away in London in the 60s," she tweeted.

"My crying sisters and I held hands, opened one and the whole thing was about how much he missed shagging her, apparently a bit of a goer. Didn't read the rest."

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