Honouring the milestone occasion, Holly, 41, revealed the secrets of her wedding day in a rare interview shared on the website of her lifestyle brand, Wylde Moon. Holly said: "It feels like a very long time ago, we have been married 15 years this year so it feels very special.
WATCH: This Morning stars' stunning weddings
"Those memories are still as fresh as they were on the day. It is a special, special time from the dress, to walking down the aisle, to the smell of those flowers that you will never forget, to seeing all your loved ones in one place."
In the July edition of Wylde Moon, Holly opened up about the memories of being Maid of Honour at her sister's wedding, issuing a key piece of advice for future bridesmaids-to-be.
Holly shared a throwback photo of her wedding day to Instagram
"One piece of bridesmaid advice – definitely don’t over-cook it the night before so you can make sure your bride goes to bed feeling relaxed, not trollied," said Holly.
Reminiscing on her sister Kelly's special day, Holly admitted: "The stress of prepping for a wedding in our parent’s garden, meant that all the bridesmaids piled down the road to the pub to let off some pre-wedding steam for rather longer than we ought to," before issuing an apology to her sister: "Sorry Kelly!" Oops!
Holly advised brides-to-be to take it easy on their pre-wedding night
The wedding memories continued on Sunday as Holly shared a rare photo from her wedding day to Wylde Moon's Instagram page - and fans couldn't get enough of the love-up duo.
"They are like a fine wine, they get better with age," wrote one fan, as another sweetly shared: "Happy anniversary to you both."
"Thank you for sharing your wedding day memories, it looked like a beautiful day!" read another comment, as a fourth fan penned: "You looked like a princess Holly! Sending early happy anniversary wishes."
The couple have been married for nearly 15 years
Holly and Dan got married on 4 August 2007 in an emotional ceremony at St Michael's Church before hosting their wedding reception at Amberley Castle in West Sussex.
They went on to welcome three children: Harry, 12, Belle, 10, and Chester, seven. "I’ll never forget the overwhelming feeling of love that hit me as I walked into the church and everyone turned around and smiled," Holly said.
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