Garth Brooks is one of the biggest stars in country music, but he's always put his family first.

On Oct. 26, 2000, Brooks -- at the height of his career -- dropped a bombshell on the music world: After 18 No. 1 hits, the GRAMMY-winning singer-songwriter announced that he was retiring from music to focus on his family. The music legend has three daughters with ex-wife Sandy Mahl (Taylor, 23, August, 21, and Allie, 19), and he wanted to make sure that he was there for their important moments.

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"Sandy and I were separated and I'm staring at three kids that I don't know," Brooks told ET, explaining his decision 15 years ago. "They have my last name. I love them to pieces. They're everything to me, but I don't know anything about them. But little did I know that that bad thing was going to be a good thing, because then it's just tie the handkerchief around your neck, get your fork and knife, and just dig in and find out so much stuff about them. And the next 15 years of my life would be the best 15 years of my life, because I got to do that."

Brooks became a grandfather in 2013 after daughter August gave birth to a baby girl named Karalynn. While Brooks hasn't gone overboard in showering the toddler with gifts just yet, he assured ET that he has a system.

"She's only two," Brooks said. "So all these other fools are spending all their time right now investing, trying to win her. She doesn't know what's going on yet. The second I see in her face that she realizes what's going on. G is moving in. They have no idea the storm that's waiting for them!"

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After splitting from Sandy, Brooks married singer Trisha Yearwood in 2005, but he's still in the honeymoon phase a decade later.

"I'm married to Trisha Yearwood, so there's nothing left possible that I could want for right now," Brooks said.

For his admirable character, Brooks was awarded the ET Icon Award. The distinction was created to honor stars who have made a huge impact on our audience over the span of decades.

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ET's Nancy O'Dell presented Brooks with the award in front of a sold-out crowd of 15,000 screaming fans.

"Miss Nancy O'Dell has been here since day one," Brooks said. "I'm going to hang on to this."