How a school project led one student to discover her dad wasn't her biological father

Every family has deep, hidden secrets -- but it's not that often they're uncovered in biology class.

Twitter user Anya Hettich, 19, has revealed how a science experiment led her classmate to discover her dad wasn't her real father. And it doesn't stop there: turns out her biological father is actually her uncle.

No joke.

Hettich -- who attends California State University -- took to the social media platform to tell the story of the student in question, revealing it all started with a discussion about blood types during an 8am lecture.

In several tweets, she detailed her classmate's confusion when she discovered her blood type didn't make sense. Her father was blood type O, while her mother was A, yet she was AB. 

https://twitter.com/anyahettich/status/966368212664303617

And this is where things start to get out-of-this-world crazy. 

If you thought it couldn't get worse, keep reading. 

https://twitter.com/anyahettich/status/966369201991557120

So, not only has she discovered this majorly dark family secret (in, er, a biology lecture?!) but said secret has proceeded to change the course of her life forever.

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Not to mention the toll it's taken on her dad, who, we guess is now her uncle? While we can only speculate, it's likely this is all new to him, too. And who even knows how her uncle feels about all this. 

The takeaway? If you've got skeletons in your closet, tell your kids before they start high school. Because as long as science is in the curriculum, it's possible your deepest, darkest secret will come back to haunt you.