After a vicious stabbing, a 17 yo Queensland boy made a 'horrific' confession to his aunt.

Last week a 12-year-old girl was allegedly stabbed 20 times in the face with a box cutter knife as she walked through a tunnel on the way to school in Kingston, south of Brisbane.

It was a completely random, devastating attack.

Now the aunt of the 17-year-old boy accused of stabbing the young girl, has spoken about the moment her nephew allegedly confessed to her.

Speaking to 9NEWS, the woman said she was “horrified” when he confessed.

“I googled it and I said ‘it’s not that, is it?’ And he nodded his head.”

“I just called the police straight away,” she said.

Following her call to the police, the accused allegedly ran away from the house, but was caught shortly after.

“My heart goes out to the family of that little girl,” the aunt added.

“She’s still a baby,” she said.

The aunt added that she had never seen him act violently, but that he had a history of mental illness. She said her nephew allegedly “thought they were someone else”.

The 17-year-old boy has been charged with acts intended to cause grievous bodily harm.

Court proceedings are closed to the public, and the young girl is in a stable condition after undergoing surgery.