ST. CHARLES • A teen mother who told police someone had kidnapped her toddler really gave her son away to a heroin user, police said.

Desiree Ann-Marie Cozzoni, 18, told police she gave the child up because she wanted to live the life of “a normal teenager.”

Cozzoni has been moving from place to place, often living with a heroin user who police say stayed at motels because she was homeless, unemployed and had lost custody of her own children.

The drug user bought and used heroin daily, often in Cozzoni and her son’s presence, police said.

Earlier this month, Cozzoni signed over custody of her 16-month-old to the woman on nonlegal documents. Cozzoni even changed her phone number the week of Oct. 6 to prevent the person caring for her son from contacting her, according to court documents.

Later, Cozzoni claimed the woman had kidnapped her son.

Cozzoni is facing three misdemeanor charges: making a false report, endangering the welfare of a child and unlawful use of drug paraphernalia.

While police were booking Cozzoni, they discovered a pipe containing marijuana residue in her purse, police said.