Audrey Wright was arrested Saturday, charged with abuse and neglect of a child.
Police say the 2-year-old walked across Merrimac Trail, which is right next to their house, then ran in front of a truck before someone stopped him.
Wright told NewsChannel 3 he was able to slip out without her realizing, and it could have happened to anyone.
Wright says she was doing housework at the time when her sister spotted him outside and brought him back in.
"If anything would have happened to my son I would die. I can't even imagine something happening to him," Wright said.
She says the arrest came as a shock. Police say one of the reasons they decided to charge her is because they were called to her house last month when the toddler got outside, but didn't file any charges then.
Wright says she's doing what she can to keep it from happening. The toddler can unlock the door, so they had new locks installed that he can't reach. Unfortunately, Wright says on Saturday the door had been left unlocked by another family member.
She'll be in court for a preliminary hearing in Dec.