"American Idol" season one alum Nikki McKibbin has passed away at the age of 42.

The Texas native joined the reality singing competition in 2002 and reached the final three alongside runner-up Justin Guarini and the season's winner Kelly Clarkson.

Moreover, the news broke after Guarini posted a black and white snap of his fellow "Idol" contestant while confirming the death of the 42-year-old.

In a lengthy Instagram post, the "Justin from Kelly" star paid tribute to his fellow "American Idol" contestant. He began his heartfelt message by describing McKibbin as a "fiery, funny lady" who could belt out a "hell out of a rock song" with her "twangy Southern wit."

 
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 @realnikkimckibbin was a fiery, funny lady who could sing the Hell out of a rock song with the same kind of ease and command she lovingly used to cut you with her twangy Southern wit. ⁣ ⁣ Even in our 20’s when we were on American Idol together I could tell that she’d had a challenging life, and that not that many people had been kind to her along the way...⁣ ⁣ ...but I’ll never forget the day that her idol, Stevie Nicks, sent her flowers with a card that said “You are the Gypsy that I was...”. Nikki was on cloud nine and the joy and excitement that radiated from her was infectious. After the kind of emotional beating she took at the hands of the masses, she deserved to feel good about herself, even for a little while. ⁣ ⁣ Rest well, “Gypsy”...and thank you for the laughter, merciless teasing, strength, vulnerability, love and friendship you showed me during our time together in the spotlight. #rip #americanidol A post shared by  Justin Guarini (@justinguarini) on Oct 31, 2020 at 3:48pm PDT

 
The singer-turned-producer went on and shared she "had a challenging life" and "not that many people had been kind to her along the way."

Despite the circumstances, the "Fast Girl" actor recalled how thrilled Nikki was after receiving a special gift from her idol, Stevie Nicks.

"But I'll never forget the day that her idol, Stevie Nicks, sent her flowers with a card that said "You are the Gypsy that I was." Nikki was on cloud nine and the joy and excitement that radiated from her was infectious. After the kind of emotional beating she took at the hands of the masses, she deserved to feel good about herself, even for a little while," he wrote.

Guarini concluded his message by thanking his former co-contestant for the friendship and the happy times they shared on the show.

"Rest well, "Gypsy"...and thank you for the laughter, merciless teasing, strength, vulnerability, love and friendship you showed me during our time together in the spotlight. #rip#americanidol."

Former "American Idol" Contestants and Fans Pay Tribute To Nikki McKibbin

Following the saddening news, fans flocked to the comment section and sent their condolences to McKibbin.

"That's terrible! I still remember her singing Black Velvet on Idol & said man she's going to go far! Rip," one posted, while a second user described the late singer as a "unique and talented" person.

"I loved her. She was so unique and talented. So so sad."

Meanwhile, "American Idol" Season 5 third placer Elliot Yamin expressed the same sentiment, saying "Just read about her. So sad to hear! Thanks for the post, Justin!"

Nikki McKibbin Died Due To Brain Aneurysm

On the other hand, Redeye Radio host Gary McNamara confirmed in a tweet that her longtime friend died due to brain aneurysm.

"She is on life support after suffering an aneurysm. They will end life support tonight. Please pray for her husband Craig and family. I am heartbroken," he wrote alongside a throwback photo of McKibbin during her "AI" days.

It's no secret that the Texas-born singer struggled with alcohol and drug addiction in the early stages of her career.

After her appearance on the long-running singing competition, she also starred in another reality show in 2008.

McKibbin appeared in "Celebrity Rehab with Dr Drew" as she sought help for her alcohol and cocaine addiction.

Aside from this, she also starred on "Sober House," Bravo's "Battle of the Network Reality Stars," and "Fear Factor."

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