In candid footage, the dad-of-three could be seen tenderly looking after his youngest as the supermodel passed by on the top of a double-decker bus celebrating the 1990s. Pointing at Kate, Prince William could be seen mouthing excitedly: "Look it's Kate Moss!"
WATCH: Prince Louis enjoyed the Jubilee Pageant
Dressed in a striking Union Jack jacket, the 48-year-old looked fittingly patriotic as she celebrated the Queen's 70-year-reign.
Alongside the likes of Charlotte Tilbury and Naomi Campbell, the British model appeared in high spirits as she enjoyed the festivities. Other guests included violinist Vanessa May, hair stylist Sam McKnight, model Erin O'Connor, and Bridgerton star Phoebe Dynevor.
Kate Moss made an appearance on the Pageant's 90s bus
The bus featured scenes from the decade with images from Harry Potter books and '90s ad campaigns to mark the memorable period. The bus made its way towards Buckingham Palace blasting out top hits by The Spice Girls and Oasis.
Prince William and George were joined by Kate, Charlotte, seven, and Louis, four. The Cambridge family were delighted by the impressive £15million procession which made its way through the streets of London.
Prince Louis shared a special moment with his grandfather, Prince Charles
The start-studded pageant was split into four acts: For Queen and Country with a military parade; The Time of Our Lives which explored seven decades of culture, music and fashion; Let’s Celebrate telling the story of the Queen’s life in 12 chapters with corgi puppets and carnival creations; and the Happy and Glorious musical spectacle which saw icons from the music, comedy, film and arts world.
Dressed in bright green, the monarch made a memorable final appearance on the Palace balcony to witness Ed Sheeran singing the national anthem with a choir made up of nearly 200 celebrities.
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