NEWPORT, N.H. (AP) — A New Hampshire toddler, barefoot and clad only in a nightgown, was found dead early Monday in bitter cold weather just feet from her front door after she managed to get out of her house and couldn’t get back in.

Police in the small town of Newport said they received several 911 calls around 7:10 a.m. about an unresponsive child who was not breathing. When they arrived at the two-story residence, they pronounced the girl dead. A preliminary investigation found the child, identified by family as Sofia Van Schoick, had left the house on her own and “was not able to regain entry,” said authorities.

Police Chief James Burroughs said they took the temperature at the scene, and it was 8 degrees below zero. Later, Burroughs said the child died as a result of “exposure to the elements and hypothermia which are consistent with the autopsy results.”

“I don’t believe it was too difficult for the child to get out,” Burroughs said, adding that her death appears to be accidental.

The toddler’s grandfather, Lindsay Van Schoick, said the family is still trying to understand what happened.

“It’s rough,” he said. “It was a terrible accident, a terrible accident. She (his daughter) is doing horrible. She is doing terrible. She just lost one of her children.”

Van Schoick, who was at the Newport home, said the family had just moved into the apartment and his granddaughter may not have known her way around. He also said the front door leading outside was easy to open and the family had not had time to put deadbolts on the entrance.

“I don’t think she made it up the stairs. They found her at the bottom of the stairs,” he said. “There are things we will never know. We’ll never know what happened.”

Burroughs said the accident remained under investigation by the police and the Sullivan County Attorney’s Office and that it had been referred to the state Division for Children, Youth and Families, as is routine in cases like this. Among the things that will be looked at are how the child got out of the house and whether there were proper safeguards to prevent it, he said.

“Certainly there are things parents can do to protect their children better and prevent people coming or going from your residence,” he said. “Those safeguards that seem common and obvious to some are not always that way for others. Accidents happen where either you forget to put locks in or chains on your doors or dead bolts to prevent this from happening.”

WMUR-TV reported a woman and her boyfriend who lived next door heard cries around 4 a.m. Monday but didn’t see anything. They went back to bed and the woman later found the girl at the bottom of the stairs leading to the child’s apartment.

“I was coming out of my kitchen and looked out the window. I saw a woman standing on the porch, a gentleman in the driveway and what I thought as a doll laying facedown next to the stairs,” said Charlotte Caron, who lived in the same house as the woman and her boyfriend. “All of a sudden I heard a scream. I saw a second woman come out of the house, grab the child and go back inside.”

The toddler’s grandfather, who lost a son five years ago, said the death of a girl he described as “very intelligent, precocious, very stubborn and adamant” has hit the family hard.

“She was a very special kid,” he said.

Alan Ayotte, a neighbor of the family who lived in the same house, said he had met them briefly and they “seemed to be fine, decent people.” He never heard anything overnight and only learned of the accident when emergency officials arrived early Monday.

“It’s just unbelievable that something happened like that,” he said. “It’s too bad that someone couldn’t have prevented it.”