'American Sniper' Chris Kyle’s Children Speak About Their Hero Dad’s Death for First Time: 'I've Grown So Much' (Exclusive) 

Strangers often come up to Colton and McKenna Kyle to tell them how much they admire their father, decorated Navy SEAL Chris Kyle, the military hero known as “The Legend” for the 160 confirmed kills he made while protecting his fellow soldiers. 

“They say, ‘You look just like your dad,’” Colton, 19, tells PEOPLE. “Every single time.”

Those who knew Chris will share a personal encounter, since he “touched so many people personally,” says Colton. 

Most of the time, though, “The number of people who come up to me who have never met him and talk about the way his story impacted them amazes me,” says Colton.

Chris first became known to the public with his 2012 New York Times bestseller, American Sniper: The Autobiography of the Most Lethal Sniper in U.S. Military History.

He became world famous with the blockbuster 2014 Clint Eastwood-directed movie, American Sniper, starring Bradley Cooper as Chris.

The film gives an in-depth look at Chris’ life on the battlefield in Iraq and his marriage to his wife, Taya Kyle, but also his tragic death.

On Feb. 2, 2013, Chris, who was 38, and his friend, Chad Littlefield, 35, were shot and killed on a Texas gun range by a former Marine they were trying to help. The shooter, who claimed he had mental health issues, was convicted in 2015 of murder and sentenced to life in prison without the possibility of parole.

Ever protective of her children with Chris, Taya, now 49, shielded them from the public eye in the years after their father died. Now that they're older, they say they feel ready to open up publicly for the first time about life with their hero father, how his murder affected them, their plans for the future and all they’ve overcome.

“Through adversity, through fire, gold is refined,” says Colton. “I am a better man today than I would have been if I had not lost my father, especially at the time that I did. I have grown so much spiritually and emotionally.”

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For McKenna, 18, who was often at her dad’s side with her tiny hand in his, or holding onto his leg, losing him was blindingly painful, causing her to fixate on the negative in life. “But I'm doing well now,” she says. “I'm learning to see the good in the world again.”

Life without their dad

Colton and McKenna have nothing but good memories of their hands-on dad, who always made time for his children. “He was so joyful,” says Colton. “And lighthearted. He liked to pull pranks on my mom and on us."

So when his father was killed, "I took his death so incredibly hard," says Colton.

For McKenna, losing her father “was devastating to me," she says. “My main coping mechanism was to look at everything as negative so I wouldn't feel something I thought was perfect was taken away again." 

Therapy, their strong family bond and their religious faith help them through the most difficult days.

After her dad was killed, “I had an idea in my head that God's love was performance-based,” says McKenna. “That if I wasn’t perfect, he would love me less. But I don't feel that way anymore."

Her Christian faith "is definitely helping me," she says. "That's been a bigger help than everything I've tried in the past.”

Upholding a hero's legacy

Colton graduated from high school last year and is taking a gap year by assuming stewardship of the American Sniper brand, which currently sells hats and apparel bearing the American Sniper logo. “My mom has allowed me to move forward with it and see everything I can do with it,” he says. 

He says he feels honored to carry on his father’s legacy. “His values and what American Sniper stands for are duty, sacrifice, patriotism, being God-fearing, freedom, family and excellence.” 

Besides selling merchandise, “I'll be exploring lifestyle gear and serving active military and veterans through the brand.” That includes giving a portion of the proceeds to The Taya and Chris Kyle Foundation, started in 2014 to strengthen first responder and military marriages.

McKenna, who is graduating high school in late May, says she is considering a career in psychology to one day become a counselor at the foundation. To explore her interest in law enforcement, she volunteers as the social media representative of Tarrant County Sheriff Bill Waybourn. “I show the behind-the-scenes of what law enforcement actually does, showing things like the forensic and canine units," she says.

“That’s really exciting to me. And it's also something that my dad was interested in," she says. "So I think that it's kind of carrying on his legacy.”