Authorities told multiple media outlets Tuesday that 26-year-old Kathleen Salling also left a 4-month-old boy asleep in a crib when she left home.
A couple driving down state Highway 90 saw the boy running down the road in only a pajama top and a diaper around 11:30 p.m. Sunday.
The boy helped police find his home. The front door was still open.
Authorities say Salling first said she left to help a friend.
Salling was charged with unlawful neglect of a child. She was in the Horry County jail Tuesday night. It wasn't clear if she had an attorney.