Royals

Duchess Catherine's touching tribute to Diana as she introduces new baby to the world

A lovely nod to the mother-in-law she never knew.

As she left St Mary's Hospital with her newborn son, Catherine, the Duchess of Cambridge, chanelled Princess Diana in a subtle but special way.

Despite having just given birth, Duchess Catherine looked flawless in a red Jenny Packham dress with a white collar, almost identical to the dress Princess Diana wore after giving birth to Prince Harry.

Kate never met Diana, who tragically died at the age of 36, but her clothing choice is a very deliberate nod to the mother-in-law she never knew.

Prince William and the Duchess of Cambridge with their third baby, a son who was born in St Mary's Hospital on April 23, 2018.
Prince William and the Duchess of Cambridge with their third baby, a son who was born in St Mary's Hospital on April 23, 2018.
Princess Diana and Prince Charles with baby Harry, born September 15, 1984.
Princess Diana and Prince Charles with baby Harry, born September 15, 1984.

Prince William, who was 15 when his mum died, talks to Prince George and Princess Charlotte about "Granny Diana" regularly.

In a recent documentary, Diana, Our Mother: Her Life and Legacy, the Prince said he has lots of photos up of her in his home.

"It's hard because obviously Catherine didn't know her, so she cannot really provide that — that level of detail," he said. "So, I do [when] regularly putting George or Charlotte to bed, talk about her and just try and remind them that there are two grandmothers, there were two grandmothers in their lives, and so it's important that they know who she was and that she existed."

In the documentary he also joked that Diana would have taken to being a grandmother a bit too well.

"She'd be a nightmare grandmother, absolute nightmare," he said. "She'd love the children to bits, but she'd be an absolute nightmare. She'd come and go and she'd come in probably at bath time, cause an amazing amount of scene, bubbles everywhere, bathwater all over the place and — and then leave."

That assertion was backed up by Sarah Ferguson, the Duchess of York, who in this 2015 interview said Diana would have been the "naughtiest" grandmother.

"[Diana] would have just been the naughtiest, funniest and the best ever just because she loved her boys so much and she would be so proud of all of them and what they've achieved," she said.

Before Princess Diana's untimely death in 1997, the Duchess of York was exceptionally close to the Princess, who was also her fourth cousin.

WATCH: Prince William and Duchess of Cambridge leave hospital with their newborn son