CLAYTON • A teenage nanny broke more than a dozen bones of the infant boy she was caring for, police said Thursday.

Amanda Eisele, 19, of the 5700 block of Wells Road in south St. Louis County, cared for the baby from May 12 through June 18.

During that time, the baby, 2 months old, suffered 14 rib fractures, two broken arms and a broken leg, according to court documents.

Eisele was charged Monday with one count of second-degree assault. Her bond has been set at $25,000. Police expected her to turn herself in sometime Thursday.

St. Louis County Sgt. Gary Guinn said Eisele told police that she assaulted the child because she would get overwhelmed when he cried.

Guinn said Eisele had no experience as a nanny and said she had posted a profile on a website after her parents hounded her about getting a job. The site, www.care.com, allows caregivers to post profiles of themselves to garner business for everything from caring for seniors, pets, children, homes and adults.

The baby's parents, of the 7200 block of Emerald Forest Drive, fired her after only about three weeks because they "had bad vibes about her," Guinn said.

They then noticed their baby was favoring one arm over the other and took him to the doctor, who found the child's arm had been broken and recommended more testing at St. Louis Children's Hospital. Medical personnel discovered multiple fractures in various stages of healing.