The royal posted a video to social media to mark the weekly event's start, which aims to raise awareness for mental health in young people.
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In her video, Kate urges children to share their feelings and not keep them bottled up, especially during a challenging time when schools are closed because of the Covid-19 pandemic.
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She says this year's children's mental health week is all about expressing yourself about finding creative ways to share your thoughts, ideas, and feelings.
She also spoke to parents in the clip as she said it's just as important for them to talk to someone.
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