 girl finds out that man is actually her father, realizes what mom did. She tried to get her to quieten down. But Lydia was lost in her own world of debate and defiance. The theory is wrong, she quipped. She gently tugged at Lydia's sleeve until she looked at her. Lydia's eyes were full of fear and panic. The entire class was watching as her hands began to shake. 19-year-old Anya Headich from San Bernardino was a student at California State University when something happened in the biology class that would change her life forever. And before she could understand the consequences of her actions, she decided to document the entire incident on Twitter. Soon, the entire world would know about her devastating discovery. One fateful day in late February 2018, Anya and her fellow students were learning about blood types in their biology class. Their lecturer was explaining that blood types are genetically passed on from parent to child. Anya enthusiastically took notes and absorbed everything she was taught. It seemed like any other lesson. But it was far from it. After the professor finished explaining the genetic formation of blood types, Anya's best friend, Lydia, raised her hand. Anya listened as she claimed that the lesson had made no sense to her and she was struggling to understand it. Lydia looked at Anya in confusion. She's a smart girl, so why was she having trouble understanding? Anya began to explain what the issue was in front of Lydia and the entire class. She confidently argued a fault in her teaching, explaining that her father's blood type is O and her mother's blood type is A, so how could hers be AB? The only logical reason? An error in the professor's theory. Gently, the professor explained that that was impossible, and if her blood type was AB, it defied science. Then the professor advised Lydia to double check her parents' blood types again when she returned home after class, and they could talk about it again. But Lydia was insistent. Anya listened in confusion as her best friend argued to their professor that she knew for a fact that A and O were her parents' blood types. Surely, there must be some sort of mistake. The professor sighed as she went to the whiteboard and drew a punnett square for everyone to see. The professor used the diagram to explain further why it was absolutely impossible that Lydia's blood type was AB if her parents were A and O Anya and the entire class were now watching Lydia, as her face started to show concern. She looked to Anya. Anya understood the way that blood types are genetically passed from parent to child. She knew that when the professor showed Lydia the punnett squares, it was indisputable. Anya understood the implications of this and tried to telepathically comfort her friend and get her to quieten down for her own sake. However, Lydia seemed lost in her own world of debate and defiance. Contemplating what the punnett square actually implied wasn't an option for Lydia. There was something very wrong here. And that fault rested on the professor's shoulders. She insisted she was wrong. In Lydia's mind, she was living proof that the way the professor was conducting the test must be wrong. But even as she argued, a nauseous ache began to grow in her stomach. Anya knew she had to calm her friend down so she reached out her hand and gently tugged at her elbow, signaling her to quiet down. She looked at Anya with bewildered eyes that immediately fell to the floor. Anya watched as Lydia's hands began to shake uncontrollably. She looked back at the punnett square on the board with fear written all over her face. But maybe the girl had simply gotten her parents' blood types wrong. Lydia visibly pulled herself together and muttered that she'd go home and check with her parents again. She clearly had the wrong information. That was the simplest solution. Surely, she had her parents' blood type wrong all along. They'd tell her what went wrong here and then everything would make sense. But things were about to get much, much worse. Anya waved Lydia home with a heavy sense of dread. She couldn't shake the feeling of apprehension and something bad about to happen to her best friend. On the one hand, she had the information her parents had given her. And on the other, cold scientific proof that what they'd told her was a lie. Did she get this wrong? Or was there something far more sinister at play here? The next day, Anya and Lydia sat down at their desks and waited for the biology class to begin. But before the professor could even start the lesson, Anya was surprised to see Lydia stand up in front of their 243 classmates as she made an announcement. Anya looked around at all of the eyes watching her best friend as she made her startling confession. Taking a deep breath, Lydia began to reveal exactly what had happened when she had confronted her parents about their blood types the day before. She asked them how it was possible that her blood type was A B and theirs was O and A. She explained what her professor had shown her and why it was absolutely impossible. After a moment of silence, Lydia's mom painfully confessed. Lydia continued to tell her entire class the shocking truth that her mom had told her. She revealed that the reason why Lydia's blood type was A B was because she had an affair with her husband's stepbrother. Lydia's world turned upside down. The man that was her stepuncle was really her biological father, and the man who she called dad was actually her biological stepuncle. Anya listened, gobsmacked as she tried to imagine what Lydia was going through as she told her story. Lydia had been lied to for her entire life. Her reality was as unbelievable as a movie script. Lydia had tried to argue with what she knew in her heart when she argued with her professor, but now she knew the truth. But, did Lydia's father know it? He listened skeptically as Lydia explained to her father exactly what her professor told her. Blood types are based on the existence or non-existence of certain A or B antigens in red blood cells. And a blood type contains only the A antigen, A B blood type contains only the B antigen, and an A B blood type possesses both. However, an O blood type possesses neither A nor B antigens. Which is what he was. When a couple conceives a child, each parent contributes one of their own A B O genes to the baby. But not all blood types are equal. The A and B genes are dominant, and the O gene is recessive. When an O gene is paired within a gene, the A, wins out. The child's type will be A if both dominant genes A and B are paired, the child's type will be A B. After Lydia finished, he burst into tears. Lydia explained that her father hadn't known about the affair. Her mother had done such a good job of hiding it that he never even suspected that Lydia wasn't his child. And now that the secret was out in the open, he just couldn't bear to be with her anymore. Lydia told her entire class that her parents were getting a divorce. As for Lydia, Lydia's life had been turned upside down in front of her entire class, and all because of a simple biology experiment. Anya wholeheartedly regretted posting her friends' shocking discovery online for the whole world to see. She had no idea how the mystery would unfold at the time or the attention her posts would garner. Regardless, they remained good friends.