The Duchess of Cambridge made a private visit to her eldest child’s school this week to help promote children’s mental health.

According to Hello! UK, Kate Middleton was at Prince George’s St. Thomas’s Battersea to attend a speech by mental health activist Hope Virgo as part of Mental Health Awareness Week.

Virgo posted about the encounter with the Duchess on Instagram, who spoke with her after.

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“This morning I spoke at Battersea School and it was absolutely amazing and a real honour to have the Duchess of Cambridge, Kate Middleton, attend to hear me speak,” she wrote. “We had a lovely chat at the end about all the work she is doing on mental health. And because you can’t take photos you get these wonderful dogs who are so well looked after at the school. What a fantastic day!” The post has since been deleted.

Mental health is a topic that Kate is very passionate about having launched both Mentally Healthy Schools, which helps students and staff access mental health support, and Heads Together with Princes William and Harry.

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More recently, the fab four announced Shout, a text messaging hotline for those who need someone to talk to.

William and Kate were also awarded the Gold Blue Peter badge in 2017 for their work with mental health awareness.