Dalton Barrett, the son of Bryan and Heather Barrett, is alert and doing much better this morning at Vanderbilt Medical Center. 

In fact, Bryan said his son was up with a smile at 4:00 o'clock Tuesday morning. 

Physicians still do not know what caused the problem, but examinations are continuing.

Dalton was unresponsive Monday when his mom attempted to wake him to get ready for school. Rutherford County Emergency Medical Services rushed the 14-year old to St. Thomas Rutherford Hospital. He was put on a ventilator and then taken to Vanderbilt in Nashville. 

Physicians earlier noted that he may have had a seizure overnight as a result of a type of virus. However, that has not been confirmed. 

Bryan and Heather don't know much more than when the frightening journey began, but they do know Dalton is smiling, awake and alert. 

Bryan said, "Despite no sleep Heather and I are doing much better now." 

He noted that the family has been encouraged and so appreciative of the many texts, e-mails and prayers.