They say the suspects, 14-year-old Kawanis Trotter and his cousin, 15-year-old Roddee Daniel, lived near the victim.
Detectives found Walker's Xbox, purse and cell phone when they arrested the two teens.
The teens face life in prison if convicted. Wisconsin law allows any murder suspect over the age of 10 to be tried as an adult.
A vigil was heldby family and friends in Kenosha Friday night for the victim.