Police say an 8-year-old stabbed his 10-year-old brother in the back around 2:30 a.m. Tuesday. It happened in the 88 hundred block of Coyle Street, near the intersection of Joy and Greenfield roads.
Police say the boys had argued earlier in the day. The 10-year-old woke up with a pain to his back, and discovered he had been stabbed.
The mother was at home at the time sleeping, thinking her children were also asleep. Two other boys, ages 7 and 11, were also in the bedroom at the time of the stabbing.
Police say child protective services and the child abuse unit are involved in the investigation. The 8-year-old boy is also undergoing a psychiatric evaluation.
His brother's injury was not life threatening, and he is expected to make a full recovery.
This is a developing story. Stay with FOX 2 for updates.
UPDATE: Story was updated to reflect the victim's age as 10 years old, not 9 as initially stated.