Simplify the following text for a Grade 0 native English-speaking person.
Original: Upon her return to the United States , Handler reworked the design of the doll ( with help from engineer Jack Ryan ) and the doll was given a new name , Barbie , after Handler 's daughter Barbara . The doll made its debut at the American International Toy Fair in New York on March 9 , 1959 .
Simplified: Barbie is a toy doll .