Nathan Paape (left), Antonio Barbeau (right) charged with Barbara Olson's murder.
SHEBOYGAN, WI (CNN/WDJT) -- The attorney for a Wisconsin teen charged as an adult for allegedly killing his great grandmother wants the case moved to the juvenile justice system.
George Limbeck says his 13-year-old client's brain is not fully developed and he lacks the decision-making skills of an adult.
Antonio Barbeau and Nathan Paape, both 13, are charged with the killing.
Police say the duo murdered 78-year-old Barbara Olson, stole jewelry from her house and took the victim's car to get pizza.
Both teens are jailed on $1 million bond each.
The district attorney has said he's never prosecuted suspects so young.