To mark Kelly's 43rd birthday on Saturday, the This Morning presenter, 41, shared a sweet snap of herself alongside her brunette sister with her 7.8million followers.
The sweet tribute came as the sisters both celebrated a win for Holly's spiritual business Wylde Moon - of which Kelly acts as Managing Director of the brand.
"Happy birthday to my beautiful sister @ladywilloughby …. Love you so so much… always [love-heart emoji]," Holly captioned the cute picture of the siblings embracing in front of what appears to be an outdoor pop-up bar.
In the image, the Dancing on Ice presenter can be seen flashing a big smile to the camera, as she wraps her arm around her lookalike big sister.
"Apart from the blonde /brunette- twins," one of Holly's followers noted in the comment section - with another agreeing and adding: "You look so alike in this picture! Happy Birthday."
Holly and Kelly enjoy a super-close bond as sisters - even able to work together on all things Wylde Moon.
Prior to turning 43 on Saturday, Managing Director Kelly took to Instagram to celebrate the business being honoured with a 'Newcomer' award for one of their brand's fragrances.
"Full of happy tears today. What a wonderful thing to happen @wyldemoon @hollywilloughby @vicky.staines @fragrancefoundationuk," Kelly captioned an image displaying the honour from The Fragrance Foundation UK.
TV presenter Vanessa Feltz was one of the many to congratulate the sisters, writing: "Well done but I’m not surprised. The fragrance is enchanting."
Holly launched her first perfume via her business Wylde Moon back in February - with many fans wary of the steep price tag attached to a small bottle.
"Tomorrow! My first ever perfume…Discover a scent to energise and enliven your senses… 8am @wyldemoon 08.02.22. #borrowedfromthewild," Holly teased at the time of her scent launch.
In the comments section, one follower wrote: "Wonder how much that will cost."
"I was thinking that too... I love her necklaces but they cost more than my rent [laughing emoji]," another fan agreed when musing the potential price point.
A third added: "Exactly thought she was gonna bring stuff out reasonably priced."
Another took a wild guess at the price of her new perfume, writing: "The diffusers are £45 & candles £65 so I am guessing £85+."
Described as "invigorating, elegant scent created to capture the evocative aroma of a wild country garden after rainfall", Wylde Moon's Eau de Parfum currently retails at £42 for a 50ml bottle.
Wydle Moon's 'boutique' (aka shop) also includes £40 candles, necklaces ranging from £100 - £495, earrings and Holly's book, Reflections.
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