Angelia Kelly's other three children were with her -- a 13-month-old girl, 10-year-old boy and 14-year-old boy.
Taylor and his mom were quickly caught and taken into custody.
The teenager was visiting from Chicago for her birthday.
Mom waits in car while teen robs gas station
Police say 17-year-old Elmer Taylor went to the counter demanding money from the clerk at a gas station convenience store in Greenfield, Wisconsin, Wednesday. He said his mother was waiting outside in a getaway car.
