This isn't the first time Prince George's little sister has worn the brand - Pepa & Co are same company that made the together page boy and flower girl outfits for aunty Pippa Middleton's wedding to James Mathews in 2017.
The confident young princess warned photographers they can't come to Prince Louis christening.
The 11-week old prince was christened by the Archbishop of Canterbury, Justin Welby, in the Royal Chapel at St James's Palace.More news: Cristiano Ronaldo rejects huge Chinese Super League contract offer
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Anwar Hussein via Getty Images The Duke and Duchess of Cambridge leave St. Mary's Hospital with newborn Prince Louis on April 23, 2018.
"Louis" older brother Prince George was also baptised in October 2013 at the Chapel Royal at St James's Palace.
Harry Aubrey-Fletcher: He went to Ludgrove School and Eton with William and his father is the Lord Lieutenant of Buckinghamshire.
The christening itself is quite the family tradition, Royal Central U.K. notes, adding Prince Louis also wore a replica of the now-famous Honiton lace christening gown. And Miss Lucy Middleton is a London-based lawyer and also Kate Middleton's cousin. A royal source said it had been agreed some time ago that the queen would not attend and her absence was not due to any health issues. Prince William was by Kate's side, supportive as ever.
Following the 40-minute traditional religious service, guests attended a private tea which included slices of christening cake, from a tier taken from the duke and duchess' wedding cake. When Prince Louis was born she tickled everyone with her confident waving at cameras as she strolled up the steps of the Lindo Wing.