The presenter, who has worked alongside Holly for 15 years on both This Morning and Dancing on Ice, admitted that her support over the past few years has done wonders for him - adding that readers are in for a treat.
WATCH: Phillip Schofield and Holly Willoughby make epic TV blunder
"To my bestie, if your wisdom does for everyone, what it did for me, then it's a bestseller already," he remarked on Instagram Stories. "Welcome to book club."
There's no denying how close Phillip and Holly are. Back in October, the dad-of-two heaped praise on his co-star and BFF, revealing she has not only been supporting him after he publicly came out as gay in February 2020, but also his wife Stephanie Lowe.
Phillip opened up on Chris Evans' How to Wow podcast, where he labelled Holly "astonishing". Speaking to Chris, the presenter said of his friend: "Holly has been astonishing, literally the best mate. She's serene, calming and sensible and she's balanced."
Phillip shared this sweet post following Holly's news
Meanwhile, Reflections - which will be published in October - will draw in on Holly's own experiences as she considers why we might simultaneously feel frantically busy and completely detached, the importance of listening to intuition and what it means to see yourself.
She also untangles topical and emotional issues such as body-image, burnout and control with candour, nuance and hard-won insight.
"I hope this starts a discussion and helps readers reflect on their own paths and on where they find themselves now," Holly said of the book. "Writing this book has been an intense experience; there are pieces of me between the pages.
"It's a one-off collection of personal essays, internal thoughts and stories. The time felt right to share this with you now and as our path goes on and we continue to walk along it, I can't wait to hold your hand and walk together."
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