A Colorado police officer comforted a 2-year-old girl with his own daughter’s special song after a tragic roadside crash that killed the toddler’s father.

Brighton police officer Nick Struck was dispatched Thursday to the fatal crash that killed a father and left a mother and three of four children injured.

Paramedics handed the fourth child to Struck as they worked to save the frightened little girl’s family. He thought of his own daughter as he held the crying girl, who was scratched, bruised and soaked in gasoline.

Struck pointed to the fire truck lights as he sang “Twinkle, Twinkle, Little Star” to the 2-year-old girl – the same song that he sings to his daughter when she falls down and cries.

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"In that moment, having that little girl in my arms, she fit exactly like my daughter did," Struck told Bill Hemmer on "America's Newsroom." "And one of the things with my daughter is that I always want to encourage her and uplift her and make sure that she's always built up."

Struck explained that he wanted the little girl to be as protected as possible from the terrible accident that had just happened.

"When I was talking to her, she wasn't really responding back to me, so I went to my singing skills, which are not the best and definitely not Barry White, by any means," Struck said. "I started singing to her and just kept going on and on. And that seemed to work. So when it works, you just keep doing it."

He explained that being a law enforcement officer sometimes means using your skills as a father, as a brother, as a son.

"You need to use those skills with the citizens, because that's who we're protecting and serving," Struck said.

Police believe that the family is from Illinois and was vacationing in Colorado. They say that no one was wearing a seat belt, except for one child in a car seat.

The cause of the crash is under investigation.

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