The photo, which was reshared on Tom's Stories, showed eighteen friends gathered in a park with picnic blankets, some with children and dogs, to remember their friend.
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Captioning the photo were the words: "Today was for our Dani," with a praying hands and a white love heart emoji.
Tom announced the devastating news on Instagram last Saturday on what was due to be the couple's wedding day.
Tom shared the update with followers on Instagram
He penned: "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.
"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.
Tom announced the news of his fiancé's death last week
"I will wear this ring that I was always supposed to wear as a sign of my unconditional love to you.
He continued: "I am completely broken trying to process this and 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.
Baby Bowie was born in October last year
"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.
"The most beautiful person inside and out. The most incredible soul. We have lost such a special person and I am sure we are about to see an abundant outpouring of love that reflects that. I will try to find peace in your messages and comments, but right now I am grieving and I will be for a very, very long time."
He concluded: "My darling Dani, the brightest light in any room, my world is nothing but darkness without you. I will miss you forever."
Tom and Danielle welcomed their baby boy Bowie in October 2021.
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