Stella Wu, 28, of Club Drive was arrested and charged with endangering the welfare of a child after Suffolk County police said she returned to the car as Second Precinct officers were attempting to gain entry to the 2010 Toyota Prius in the parking lot of Bed, Bath and Beyond.
The incident occurred at 9:49 a.m., police said.
Police said officers William Moldovan, Claudia Delgado and Christopher Fezza had responded to the lot following a 911 call. Police said the toddler was in the car alone for at least 10 minutes.
The girl was released to a family member, police said.
Police said Wu is being held at the Fourth Precinct and faces arraignment First District Court Friday in Central Islip.