Elizabeth Dowdell, a nursing professor at Villanova University in Pennsylvania, said her research involves Internet safety and many have told her about texts other people tell them they made but don't remember making.
"Many parents tell me, 'My child is so connected they never leave their cellphone and they have it on their nightstand and they answer it and then they find out later they texted,'" Dowdell told United Press International.
"The cellphone buzzes and the teen picks it up as a reflex -- and in a transitional sleep state not quite asleep but not quite awake -- answers in a text and hits send and it isn't until the next day they someone will tell them about the text."
The answer can be gibberish, or it can start out OK but then turn into something nonsensical, and when they get to class the next someone will tell "You sent a crazy message last night," Dowdell said.
"It can be silly and embarrassing, but it can turn into bullying, too," Dowdell said. "But outside of the Internet issues, answering the phone during the night can result in fractured sleep which doesn't lead to the restorative sleep everyone needs."
Most children and teens don't get enough sleep -- teens should get 8.5 to 9 hours of sleep a night and most don't get nearly that much, Dowdell said.
"When teens don't get enough sleep they become cranky, grumpy, they fall asleep in school and soon it is affecting their school work and their relationships," Dowdell said.
"I suggest everyone in the family place a docking station in the kitchen or family room -- outside of the bedroom -- at 10 p.m. so everyone can get restorative sleep and to show children that the phone can be turned off some of the time."
Some teens insist they need their phone because they use it as an alarm clock, but parents can insist their child place the cellphone across the room so they have to get up to answer it and that will wake them up -- or get them an alarm clock, Dowdell suggested.