Prince and Paris Jackson, children of perhaps the world's most famous man, stepped into unfamiliar territory at the 52nd Grammy Awards on Sunday night – the spotlight.

Michael Jackson’s eldest children, who he always protected from the public eye, accepted their dad’s posthumous Lifetime Achievement Award, and while their courage brought about a standing ovation, it was clear the two had trouble getting through their speech.

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"We are proud to be here to accept this award on behalf of our father, Michael Jackson," 12-year-old Prince said, before getting choked up and stammering. "First of all, we'd like to thank God for watching over us for the past seven months. And our grandmother and grandfather for their love and support. We would also like to thank the fans. Our father loved you so much because you were always there for him. Our father was always concerned about the planet and humanity. Through all his hard work and dedication, he's helped with many charities and donated to all of them.”

Eleven-year-old Paris closed the acceptance with a few more words; however she was clearly overcome by the moment.

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"Daddy was supposed to be here, Daddy was gonna perform this year," she said quickly. "He couldn't perform last year. Thank you, we love you, Daddy."

The King of Pop also has a seven-year-old son, Blanket, who Pop Tarts is told was never slated to make an appearance.

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And if paying tribute to their late father wasn’t emotional enough, on top of that, Prince and Paris also had to return to the Staples Center, the site of Michael Jackson’s memorial last summer, and the very same stage on which their dad spent hours rehearsing  just prior to his death.

“It was sad, they were very overwhelmed and seemed confused by it all,” a source close to the Jackson family told Pop Tarts. “It took right up to the 11th hour for everyone involved to agree, but the children did really want to it. They’ve had to grow up a lot – last year at the memorial they were just little kids and now they’ve really grown up.”

According to our insider, MJ’s children are being very well taken care of by their grandmother Katherine and are coping “pretty well,” but there is some concern that the constant string of Michael Jackson tributes that have taken place since his death could be having a negative impact on their healing process.

“They’re getting tired of all these tributes, it is not letting them move on,” said our source. “It’s not healthy.”

On the note of the highly-anticipated 3-D Michael Jackson “Earth” tribute that brought together Celine Dion, Carrie Underwood, Usher and Smokey Robinson, would it have been a lot more meaningful had Michael’s brothers done the honors instead?

“Remember, there was no Michael Jackson without the Jackson Five. It was a missed opportunity not getting them (the brothers) all together for this,” added our insider. “And Berry Gordy (Motown founder) was sitting in the audience and it was disappointing that he wasn’t a part of it either.”