Los Angeles, Dec 18 (IANS): Actor Will Smith says his children -- Trey, Jaden and Willow -- have stopped taking advice from their parents “a long time ago” as they are grown ups now.

"You know, listen, I have a 23-year-old, a 17-year-old, and a 15-year-old, so they were done listening to me a long time ago," Smith told usmagazine.com.

Smith's latest film “The Concussion” sees him star as Dr. Bennet Omalu, a pathologist who makes history when he uncovers the link between permanent brain damage and the frequent head injuries professional footballers suffer from. 

Shooting the film, which is based on a true story, made Smith even more aware of the dangers of the sport, and he says watching the finished movie as a parent was a harrowing experience.

"It was a little scary because my son played football for four years and it (brain injuries) was never even was a subject. It never came up. We were concerned about him breaking his leg, or spinal injury was the big thing that all of the parents were concerned about," Smith said. 

“So it was scary to me -- it was almost as if it was hidden in plain sight. And as I started to understand the science, I knew that it was something that I wanted to deliver to the world," he added.