Published: May 08, 2011 8:05 PM EDT
Updated: May 08, 2011 5:05 PM EDT

ST. PETERSBURG, Fla. (AP) - Authorities say a St. Petersburg teenager fatally stabbed his stepfather during an argument involving the boy's mother
 
Police say 41-year-old Otis Wilson was in a physical argument with his wife Saturday night when the 16-year-old intervened. Detectives say he grabbed a knife from a kitchen drawer and stabbed Wilson several times in the torso and leg. Wilson later died at a hospital.
 
Police say the teen acknowledged stabbing Wilson but said he was defending his mother. The boy, whose name is being withheld because he is a minor, was charged with manslaughter and taken to a juvenile detention center.