THE Duchess of Cambridge has proudly debuted baby bump No.3 as she made her first public appearance since announcing her pregnancy last month.

Alongside husband Prince William and brother-in-law Prince Harry, Kate, who hasn't been seen in public since August 30, recognised the efforts of mental health workers at Buckingham Palace.

Despite reports she is being plagued from extreme morning sickness, the 35-year-old glowed as she talked with several people at the reception.

Kate Middleton has debuted her baby bump alongside Prince William and Harry at Buckingham Palace. (AP)
Kate Middleton has debuted her baby bump alongside Prince William and Harry at Buckingham Palace. (AP) Heathcliff O'Malley

However, Kate's health has forced her to cancel her royal duties and consigned her to her bed with hyperemesis gravidarum.

She suffered the same ailment during her pregnancies with Prince George and, more recently, Princess Charlotte.

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But Kate wasn't about to miss this event with the royal family strong supporters of mental health awareness.

Both Prince William and Prince Harry have been vocal about their own struggles with mental illness, especially after the shock death of their mother, Princess Diana.


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