It happened Saturday around 4pm inside the girl's home on Ninth Street in Passaic.
The little girl was rushed to Saint Joseph's Hospital and Medical Center in respiratory distress.
The girl is listed in critical condition Sunday evening, and is said to have suffered significant brain injuries.
Ackie is apparently a friend of the little girl's mother, and was was babysitting at the time.
Ackie was arrested Sunday morning and charged with 2nd degree endangering the welfare of a child and 2nd degree aggravated assault.
Bail has been set at $500,000.
The investigation is continuing and may result in additional charges.