Holly Willoughby sent a letter to one of her former teachers after the success of her recent book, thanking her for helping the presenter with her dyslexia.
The host of This Morning released Reflections last month and it is now a Sunday Times Bestseller for the third week in a row.
Willoughby told fans in an Instagram video that she recently sent a letter to her favourite teacher, Mrs Williamson, to thank her once again for all of the help she gave her at school.
She said: "Funnily enough I sent my old English teacher a letter yesterday just saying: 'Oh my god, I wrote a book, and who would have thought that was ever actually gonna be possible when I was at school?'
"I think you all know by now but I'm dyslexic so when I was at school, English was not my favourite subject at all and I found it really difficult."
Willoughby added: "So to now be sitting here as a Sunday Times Bestseller is pretty incredible and overwhelming actually, so thank you."
The 40-year-old TV presenter spoke earlier this month about her struggles with dyslexia, revealing she wasn't diagnosed until she was preparing to do her GCSEs.
On This Morning, she said: "For a long time at school I hated reading out loud because I could not read very well, I would get mixed up and I was constantly embarrassed.
"[Mrs Williamson] always took me aside. She spent a lot of time with me and really took the time. Even in break times. She would never make me feel stupid."
Willoughby explained last year in an interview with Red magazine that she still struggles and that her occasional mistakes on TV are down to her condition.
She added: "It doesn’t do what it did to me back then because I don’t let it have power. I now know that it’s all about how you package it in your head."
Reflections features Willoughby discussing the ways in which she has fought back against adversity in her life, offering strategies for readers to follow.
The book has featured on the Sunday Times Bestseller list since it was released in October.
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