A Houston, Texas couple were horrified to learn that someone hacked into their baby monitor and was using it to shout expletives and sexual terms at their sleeping daughter. According to ABC News, Marc and Lauren Gilbert heard the sound of a stranger's voice coming from their daughter's room and ran to see who was there, only to realize that the voice was coming from the baby monitor.

Marc Gilbert was washing dishes on the night of August 10 when he first heard the stranger's voice. He and his wife went to daughter Allyson's room and realized that the voice was coming from the speaker of the family's baby monitor, which was running on the home's Internet router.

The hacker had apparently used the camera to read the 2-year-old girl's name off the wall because he was calling her by name and trying to wake her up. The Gilberts' daughter, however, is hearing impaired and cannot hear without her cochlear implant being activated.

Marc Gilbert hastily unplugged the device to shut it down. The family has never learned the identity of the hacker or figured out how he broke into their system.

CBS News spoke to cyber security expert Dave Chronister, who said that parents should password protect their wireless baby monitors just as rigorously as they would any of their other wireless devices.

Chronister said that pranks like this one are often the result of teenagers exploiting unprotected or weakly protected wireless systems.

"Make sure you punch in a password and make sure it's long," he urged parents.

Watch video about this story, embedded below via ABC News:

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