This is the first time Kate has appeared in a video of this kind which was for children’s charity Together for Short Lives of which she is a patron.
Dressed in another chic outfit, Kate donned a black dress with a white collar looking absolutely radiant.
Speaking in the video, Kate says: "As Patron of East Anglia's Children's Hospices I have been fortunate to see at first hand the remarkable work that they do for children and young people with life-limiting conditions, and their families. It is simply transformational.
"There are 49 children's hospice services across the UK, all providing similar invaluable and life-enhancing care to thousands of families.
"Children's Hospice Week is a time to recognise, celebrate and support the inspirational work of those hospices, and those who provide palliative care to these children and families.
"Children's hospices provide lifelines to families at a time of unimaginable pain. The support they give is vital.”
The Duchess of Cambridge announced that she was pregnant with hers and Price Williams' first child earlier this year.
She is due to give birth in mid July.
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