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"THANK YOU ♥️ Couldn't really do anything yesterday, we've just been thinking of the incredible @bowelbabe ♥️," the Six Queens of Henry VIII actress began a lengthy caption posted to Instagram Wednesday.
"Last month, we were honoured to be part of the wonderful #nobutts campaign that she spearheads and I've since been looking back through all of her incredible campaigning to raise awareness for bowel cancer - it's just phenomenal what she's done to help people spot the signs and get help," Holderness, 38, continued.
"I truly believe what Deborah & others like her have done to get the message out - that bowel cancer can happen to ANYone, at ANY age - was a huge factor in Adele's symptoms being taken seriously & getting her seen for a colonoscopy as quickly as she was," wrote Holderness.
"Thank you for everything you've done Deborah, and for what your legacy will continue to do. ♥️ If you can, please consider donating to the incredible #BowelBabeFund that Deborah has set up to carry on her incredible, life-saving work," she concluded.
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Roberts, 43, also thanked James — who was diagnosed with bowel cancer in 2016 and recently entered hospice care — in the comments section of the post, praising her for everything she's done for those who are going through cancer.
"What an incredible woman. I cannot believe her strength and to see how much she's helping others whilst going through the hardest days of her life is incredible. #ThankYouDeborah ❤️🙌🏽 xxxx," Roberts wrote.
In addition to thanking James for all she's done for the community, Roberts opened up about how chemotherapy has affected her skin since undergoing treatment in a series of photos posted to Instagram Friday, writing, "Everything I'm going through at the moment has taught me it's good to share. I'm not the only one."
"I'm very lucky to be on this treatment but it's ravaged my skin a lot. I've shared what it's done to my hands and feet but I was too ashamed to show you my face," she continued. "I've been thinking a lot recently and I've realised that it's good to share as much as I can. What if someone else is suffering too and they think they're alone. You're not."
RELATED VIDEO: BBC Host Deborah James Pens Emotional 'Goodbye' Message Revealing She Is Entering Hospice Care
In a heartbreaking update in her health journey posted Monday, James opened up about being in hospice, penning an emotional caption on Instagram.
"The message I never wanted to write. We have tried everything, but my body simply isn't playing ball," James wrote in part. "My active care has stopped and I am now moved to hospice at home care, with my incredible family all around me and the focus is on making sure I'm not in pain and spending time with them."