The X Factor judge, 32, is currently in Barbados where her former Girls Aloud bandmate Kimberley is set to marry long term boyfriend Justin Scott today (Saturday 30 January).
And the 'Crazy Stupid Love' singer chose to send a very public message to her mate via Instagram.
Sharing a photo of the stunning pair together, Cheryl wrote: "So on this Final Friday of @kimberleywalshofficial being just Miss Walsh I am going to throw it back to this little golden nugget I don't know how I ever got so fortunate to find, share & grow the past 14 years of my life with such an amazing, beautiful, kind, considerate and genuine true friend."
Awwww, so sweet!
Cheryl, clearly talking from the heart, continued: "This journey we have shared growing from girls to young women has shaped us into the people we are today. And I could not be more proud of the woman, mother & very soon to be wife you are and have became..
"I love you soooo much. I am honoured to share with you one of the happiest days of your life. I wish you both eternal happiness, filled with love, laughter & a beautiful life with your husband to be and your gorgeous (hopefully growing soon) family..."
Cheryl also included Kimberley's fiancé in the love fest, adding: "Justin I love you & thank you forever for making her the happiest most content & best version of herself that she is today. You are one very lucky guy I love you both #walshxscottwedding."
Cheryl and Kimberley met on talent show Popstars: The Rivals when they formed Girls Aloud in 2002.
Since then, the pair have become firm friends, along with fellow bandmate Nicola Roberts.
Cheryl and Nicola are both serving as bridesmaids at Kimberley and Justin's wedding.
The soon-to-be husband and wife arrived in Barbados with their one-year-old son Bobby earlier this week.
Reports suggest that remaining Girls Aloud bandmates Nadine Coyle and Sarah Harding were not invited as the wedding is for family and very close friends only.
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