The 37-year-old shared a black and white picture of herself and sibling Lesly Marie, in which they are sporting the same identical smile, and captioned the post: "There are not enough words to describe the love I have for my little sister... she is truly a diamond in this world.
WATCH: Janette and HRVY's incredible chemistry behind-the-scenes
"I miss you more then you could ever imagine. So blessed to have you as my rock and best friend always. When no one else understands the 12 little 'Inside Out' characters in my head, you do! @missleslymarie, I love you beyond explanation and wish you the HAPPIEST OF BIRTHDAYS! You deserve the world! #MyLittleSister #WishiCouldHugYou #iLoveYou #SheGetsMe."
Lesly was quick to comment on the sweet post, telling Janette: "I love you doesn't even begin to cover it. I'm very lucky."
Janette and her sister Lesly
The Strictly star, who will be performing three dances with HRVY in this Saturday's grand final in the hope of lifting the coveted glitterball trophy, is hoping to be reunited with her siblings and parents once the show is over.
Speaking exclusively to HELLO! the star revealed that if regulations allow, she hopes to spend the festive season in Miami with her family. Otherwise, she and Aljaz Skorjanec will spend Christmas together at home in London. The festive period will also be good for Janette and Aljaz as they will finally be able to reunite after months living apart.
"I miss Aljaz so much and it's been so hard seeing him at the studio – because of the rules, I can't touch him or run over and hug him. We speak every night before I go to bed, and thank God for FaceTime," she recently told HELLO!
"Absence has definitely made the heart grow fonder for us, and I know more than ever just how much I really do love him, because I can't wait to get back home," she confessed.
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