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Holly Willoughby just revealed the secret to her youthful looks!

So that's where she got her good genes from!

Chloe Best

Holly Willoughby shared a rare photo of her grandmother in honour of her 90th birthday on Thursday - and her fans were amazed by their "amazing" resemblance. The This Morning presenter made a return to Instagram to post a sweet tribute to her "nanna", leaving her 3.8 million followers with no doubt of where she got her youthful looks from.

"Yes Nanna Willoughby... 90 today! Love ya!" Holly captioned the post, which showed her grandmother sat in an armchair holding a dessert with the words "Happy Birthday" written in chocolate. Holly's grandmother looked much younger than her 90 years, wearing a striped T-shirt, and her appearance was the subject of many comments from the TV presenter's fans.

Holly Willoughby shared a rare photo of her grandmother to celebrate her 90th birthday

One wrote: "Good grief she looks so young. Amazing!" While another asked Holly: "Omg how is your nanna 90? She looks amazing." Many others commented on the resemblance between Holly and her grandma, with one writing: "Can see the resemblance. Great genes."

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The photo is one of only a handful Holly has posted since breaking up for her summer holidays from This Morning. The 37-year-old has been spending time with her husband Dan Baldwin and their three children, but made a surprise return to the ITV show on Wednesday for a pre-recorded interview with All Saints.

Holly is on her summer holiday from This Morning

Holly commented on how "weird" it was to interview her friends as she uploaded a photo of herself and Phillip in the studio with singers Nicole Appleton, Natalie Appleton, Melanie Blatt and Shaznay Lewis. Holly, who is particularly close to the Appleton sisters, wrote on Instagram: "These beauties @allsaintsoffic are on @thismorning today... so weird interviewing your friends!"

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The presenters were chatting to the band about their new album Testament, which was released in July, but Holly got the giggles as soon as they sat down. "We're laughing already. This is going to be the hardest interview I think I've ever done!" she said. "I can't even look at you Nicole...and I feel like we've had this interview many times on a night out and now this is actually happening for real!" Nicole replied: "It's actually more nerve-wracking than a night out!"

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