The 40-year-old singer turned reality TV star explained during his interview that he hadn't addressed his brother Zach's diagnosis before because he "wanted him to be comfortable with that happening" first. And now, he is.
Zach was adopted by Lachey's mother after he and his brother, Drew, left home to start 98 Degrees. The singer explained that since Zach began school it became obvious to his mother that he wasn't leaning "in a typical way." Zach was later diagnosed with Asperger syndrome, an autism-spectrum condition, at the age of 7.
"He's referred to as high-functioning autistic. So he's verbal and able to go to a fairly typical school," Lachey explained. "He's socially different than what we perceive as normal for kids. He gets anxious and he's very focused. He hones in one on thing and he can't be taken out of it...He's a good kid, a sweet kid...He just learns differently than most people and reacts to situations differently."
Lachey went on to explain that his interest in raising awareness about the condition goes beyond his brother.
"There's just so many questions and very few answers," he said. "It's just something we have to do more research on and we have to get the answers that these families so desperately seek. Mine included."
Lachey is among nearly 100 celebrities who have autographed Gold Bunny figures to raise autism awareness. All proceeds from the Lindt Gold Bunny Celebrity Auction will benefit the research and advocacy organization Autism Speaks. Other celebrities involved in the project include Sarah Jessica Parker, Fergie, Blake Shelton, Julianna Margulies, Kelly Clarkson, Harrison Ford, Tom Hanks and will.i.am.
You can read the singer's full interview with CBS, here.