Chelle was born in NYC to Marcellino Cordero and Reva Rudick Cordero on April 21, 1954. She grew up in the Bronx. Chelle is the younger of two daughters, her sister is Barbara. She attended the "High School of Art & Design" and later Fordham University School of Liberal Arts where she studied Theatre Arts.
Under the tutelage of NYPD Detective Henry Spallone (later mayor of Yonkers), Chelle began her writing career with an article in the Bronx Press Review about a 16-year old boy who was murdered during a mugging on the NYC subway.
Chelle married photographer and AV consultant Mark Engelman in 1975. They live in Rockland County, NY where they raised their family (daughter Jenni, son Marc).