Mann also posted another photo of Hampson on his Instagram Story. In the side-profile shot, Hampson held up her phone as she seemingly took a photo of something in front of her.
Mann wasn't the only person who had Hampson on their mind Friday. That same day, Hampson's sister-in-law Helena Smith paid tribute to the late dancer on her Instagram Story by reposting a photo of them together.
In the snapshot, which dates back to July 2021, a pregnant Hampson held her baby bump as she and Smith stood next to each other and smiled with excitement.
"Baby Mann your Auntie loves ya already 💙," Smith captioned the photo at the time, to which Hampson commented, "Can't cope already 😭💙"
Just three months after that photo was taken, Hampson and Mann welcomed their first child together, Bowie Andrew Mann.
Hampson, who was a PR Executive at Knowles Communications, died on Saturday, June 18, according to a heartbreaking Instagram post that Mann shared on Monday.
"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," he wrote beside a black-and-white photo of Hampson with Bowie. "On what was supposed to be the happiest day of our lives ended in irreversible heartbreak. I feel like I have cried an ocean."
"We never made it to the [altar]; 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 continued. "I will wear this ring that I was always supposed to wear as a sign of my unconditional love to you."
Mann went on to note how he was "completely broken trying to process" the tragedy.
"I honestly don't know where to go from here, but I do know I need to use any strength I can muster for our little boy," he wrote. "I will not be a mark on the parent that you had already become but I promise I will do my everything to raise Bowie just the way we always wanted. I promise you he will know how amazing his mummy was. I promise to make you so so proud."
Hampson's family has also honored her memory across social media since her death.
Her father, Martin, said the entire family is "devastated" and that "no parent should ever have to write" a post about losing their child.
"She was the beating heart of our family, the loving, successful, intelligent daughter who always put everybody before herself, and as a result was loved by everyone," he wrote on Instagram. "She will always be my little princess, the love of mum's life, the sister Andy adored, Helena's BFF, Tom's true love, and of course, Bowie's amazing mummy. We are all devastated and utterly heartbroken."
Hampson's brother, Andrew, also took a moment to "express just what Danielle meant to me and the void she is going to leave in all our lives."
"For as long as I can remember, Danielle has been my best friend," he wrote, later adding, "The love we had for each other was immeasurable. When people who didn't know us asked if we got on well I would say perfectly, we never argued, just the very occasional brother and sister tiff."
Andrew said he had "so much pride" over what his sister accomplished in her career, but noted "her greatest achievement" was becoming a mother to her 8-month-old son.
RELATED VIDEO: X Factor Alum Tom Mann Reveals His Fiancée Dani Died on Their Wedding Day: I've 'Cried an Ocean'
Her sister-in-law also wrote on Instagram that Hampson had "so much life left to live with both Tom and Bowie."
"I can never thank her enough for her selflessness and always, always putting other people first, even when she didn't have to," Smith wrote, in part. "I looked up to you since the moment I met you Danielle, the big sister I never had and never knew I needed, a best friend. You taught me so much and I promise to use what I've learnt from you throughout the rest of my life, and to be there for Bowie always, I'm so happy I get to be his Auntie. Love you and miss you forever."
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Mann and Hampson originally intended to wed in August 2020 but had to delay the ceremony twice due to the COVID-19 pandemic.
Hampson's cause of death has not been released.