Editor’s note: Some of the details are graphic. CLEVELAND, Ohio – Homicide detectives are investigating the fatal stabbing of a 67-year-old grandmother and the stabbing of three young children. It happened 12:15 a.m. Saturday in the 19600 block of Chickasaw Avenue on Cleveland’s east side. 18-year-old Jaylen Latrell Plummer is in custody. He has not been officially charged. Plummer was taken to Cleveland Clinic with lacerations to his hands. There were two 10-year-old female victims and one 12-year-old male victim. All three are being treated at Rainbow Babies and Children’s Hospital. The Medical Examiner’s office identified the victim as Diane Madison. Police say Plummer entered the rooms of the three juvenile victims and began stabbing them while they were sleeping. Two of them were able to get out of the house and run to neighbors, where they called police. According to police, Plummer got in the shower after stabbing the children. Police say that’s where they found him. Diane Madison had multiple stab wounds. She was pronounced deceased at the scene. The FOX 8 I-Team has confirmed she is the mother of serial killer Michael Madison. One of the children stabbed is Michael’s child. Madison was convicted of aggravated murder in the deaths of three women whose bodies were found near Madison’s East Cleveland apartment in July 2013. Stay with FOX 8 for more as this story develops.