X Factor alum Tom Mann shared that his fiancée Dani Hampson died hours before they were due to wed.

Hampson was 34. TMZ notes a cause of death has not yet been confirmed.

Mann — who auditioned for X Factor in 2014 and was placed in the now-defunct band Stereo Kicks — shared revealed the news with his followers on Instagram Monday (June 21).

"I can’t believe I am writing these words but my darling Dani — my best friend, my everything and more, the love of my life — passed away in the early hours of Saturday morning, 18th June," Mann wrote alongside a black-and-white photo of Hampson and the couple's baby boy on Instagram. "On what was supposed to be the happiest day of our lives ended in irreversible heartbreak."

The couple were supposed to wed in 2020, but their plans were pushed back due to the pandemic, according to Us Weekly.

Mann addressed their beautiful relationship in his post.

"We never made it to the alt[a]r; or got to say our vows, or dance our first dance, but I know you know that you were my entire world and the best thing that has ever happened to me, Danielle," he wrote. "I will wear this ring that I was always supposed to wear as a sign of my unconditional love to you."

Read Mann's full post below:

Celebrities and other followers rushed to the comments section to offer Mann their condolences.

"I'm thinking of you non stop," Ellie Goulding wrote. "You are so strong. Here for you always. Love you xxxx." Others who reached out included the likes of HRVY and SG Lewis.

In his message, Mann promised to be there for his and Hampson's child, who was born in 2021.

Last year, the couple shared their happy news on social media and confirmed that the baby was due in October.

They welcomed their son Bowie Andrew Mann on Oct. 18, 2021.

"We are saturated with a love I didn’t know existed & one I will never be able to put into words," Hampson wrote on Instagram at the time. "You have changed our lives forever."

The couple frequently shared photos on social media smiling as a happy family.

Hampson's final post on Instagram, uploaded in May, included photos of the family on a trip to Italy.

While Stereo Kicks is no longer together, Mann has continued to work in the industry as a songwriter. He has credits on songs for Regard and Troye Sivan, and worked on Tate McRae's "You" and Rita Ora's "How To Be Lonely."

The former won him an award at the BMI Pop Awards earlier this year.

PopCrush's thoughts are with Mann and the rest of his family at this time.

Stars We Lost in 2022

See the famous icons we have had to say goodbye to in 2022, below.

More From Q98.5