It was on July 16 that the police were alerted to the incident and the teenager was arrested at the crime scene.
The following day, the sibling, a child under 15, died.
The trial began on November 25 in Solna district court and according to the so-called section seven investigation that was carried out, the girl may be suspected of suffering from a mental disorder.
The girl is also ordered to pay damages of SEK 130,000 to the guardian.
The text is updated.