Alfred Mokoena taught the unnamed girl in South Africa, and according to reports admitted to taking advantage of her.
But, after the encounter with his pupil, DNA tests later proved that they were related.
The Daily Star reports that he said: “She was young and was supposed to believe whatever I said to her.
“I am sorry for the fact that I didn’t even bother to look for her all these years.”
The girl lived with her mother and stepfather at the time of her pregnancy, and was unsurprisingly shocked to learn the gruesome truth.
Now 20-years-old, she’s worried about their child learning that his father is also his grandfather.
She said: “Now he is four years old and I am convinced that he is well because he can talk and walk.
“My only problem is how will I tell him that his grandfather is his father? That’s the only thing that worries me.”
Local reports claim that Alfred initially denied impregnating the girl to save his reputation as a teacher.
He also allegedly threatened to kill the journalist who exposed him.