Ariel Smith, 19, of Harvey was arrested Thursday, The New Orleans Times-Picayune reported.
Smith was caring for Andre Jenkins and his 18-month-old brother when she became upset with the baby, Jefferson Parish sheriff's officers said. She allegedly admitted putting the boy in the dryer after intensive questioning.
The babysitter called 911 shortly after 11 a.m. reporting that a baby at her address was not breathing. Paramedics found Andre lying on the floor, dead.
At first, Smith claimed that the boy had been burned when his older brother pushed a pot of boiling water off the stove. She eventually acknowledged she became "frustrated" with the baby, put him in the dryer and turned it on.
Smith was caring for the two brothers while their mother was at work.