Elizabeth Hurley's son has said his "heart is bursting with pride" following the release of his "big sister's book".
Damian Hurley took to Instagram and shared a throwback photo from his time as a child actor on The Royals as he celebrated Alexandra Park's success.
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The picture shows him sat on the star's lap and smiling as Australian actress Alexandra wraps a protective arm around him.
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Damian, 19, wrote: "Heart is bursting with pride! my beautiful on screen big sister @AlexandraPark1 has just released her new book and you must must must order your copy NOW!
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"This photo is from the first day we ever met in 2013, shooting our pilot of The Royals - I thought (and still think) that Alex was one of the most confident and beautiful people I'd ever met - little did I know that just a few weeks earlier, she had been diagnosed with Type 1 diabetes.
Damian shared a touching post in honour of Alexandra's book release
"At the time, I was too young to understand the enormity of this but now, having read Alex's beautiful book, I have a crazy new level of awe and respect for how this beautiful human acclimatised to both her illness and intense career without complaint and with such charm and professionalism."
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Damian then urged: "So go jump onto Amazon and search for 'Sugar High' by Alexandra Park if you feel like being truly inspired by a brave and courageous human who I'm honoured to call my family. Forever proud and forever in awe @AlexandraPark1."
Alexandra starred as Princess Eleanor in The Royals
Alexandra – who starred as Princess Eleanor in The Royals - was among the first to comment on the sweet post, admitting it had made her cry. The 31-year-old added: "Thank you SO much my darling little brother, knowing you and watching you grow into the incredible young man you are today has been an honor, just love you so much!! look at us in this photo!!!"
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