Officials at Erlanger Medical Center in Chattanooga said 16-year-old Brannon Martin has been in critical condition ever since he was airlifted Monday following a car wreck in Cherokee County, N.C., that killed two of his brothers.

Lynn Pollard, a family friend, told reporters Thursday night that Martin had surgery Wednesday to repair damage to his hip and that he seemed to come through the surgery alright. She said the teen’s parents, Gene and Becky Martin, received minor injuries in the crash and had been by their son’s side at Erlanger this week.

Braden Martin, 2, and Brad Martin, 14, were both killed in the wreck.

The Martin family, from Trion, was vacationing in North Carolina this week when the wreck occurred.