You go to school to learn – but you never expect to discover a hidden truth about your family during a history lesson.

But that’s exactly what happened to two students who realised their related when studying World War One.

In response to the Reddit thread, ‘What’s the biggest plot twist you’ve seen in real life?’, a user shared a memorable history lesson from their school years. They said: “In primary school We had a WWI memorial lesson and we were asked if anyone had any relatives who fought at the time.

“My friend brought in a picture of his great great grandfather with his wife. A girl also brought in a picture of her great great grandfather with his wife. The teacher said they looked similar. She put them side by side and looked shocked.”

With that, the entire class gathered to look at the photographs – with many coming to the same realisation. They added: “It was the same man who had kept his two wives a secret. Both had been married privately. They were cousins and didn’t know.”

Commenting on the post, one shocked user said: “And he almost got away with it!” Another user added: “A secret for almost a hundred years.” A third user said: “My dad had this same situation Talking to his friend. He starts talking about his grandpa, and his friend just goes, ‘Wait, my grandpa had the same name’. They were cousins.”

One more user added: “Any possibility of the great great grandfather being an identical twin?” It comes after another user discovered their grandma’s ‘awful’ secret following their grandad’s death. They explained how their grandad was diagnosed with dementia – and was struggling to “keep track of reality” during his final year of life.

Before bed every night, he would see a man walking around his house – but none of his family believed him when he spoke up about it. He was put into a care home shortly after, with the family putting the story down to ‘dementia’. But when a strange man showed up to his funeral, the family started to question things.

The post reads: “Fast forward to my grandfather’s funeral and a man showed up that wasn’t known by more than a few people in the family. Turns out he was an old friend of my grandmother’s who showed up to give his support. In a small town like that it wasn’t exactly an unusual thing to have random people show up to the funeral home who knew the person at some point.

“Well about a year later my grandmother lets slip that she is seeing someone, the guy from funeral. At this point nothing too odd, they got to talking at church and we thought it was sweet. Then a bit later sweet innocent old grandma mentions that it’s their third anniversary.

“Grandpa died two years prior. This man was the person that grandpa saw in his house every night. He was the reason that everyone thought grandpa was going crazy, he was the reason that my grandfather was medicated to the point of being a vegetable for the last horrible year of his life.”

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