William, Kate’s son Prince Louis, 4, steals the show at Platinum Jubilee

Queen Elizabeth II was supposed to be the star of her Platinum Jubilee — but all eyes were on her great-grandson.

Prince William and Kate Middleton’s 4-year-old son, Prince Louis, made an adorable

arrival at Thursday’s Trooping the Colour parade,

wearing his dad’s hand-me-down sailor outfit from the same event in 1985.

The little one greeted the crowd from a carriage with brother Prince George, 8, and

sister Princess Charlotte, 7, as well as mom Middleton, 40, and step-grandmother Camilla Parker Bowles.

The mini royals waved at onlookers who joined them in celebrating the Queen’s historic

70 years of service. When Charlotte took a break from greeting them,

she also put Louis’ hand down in a sweet big sister moment.