"There were all sorts of mixed emotions," Kate Middleton says of debuting her son to the world in 2013

Kate Middleton debuted all three of her babies on the steps of the Lindo Wing of St. Mary’s Hospital shortly after their births, giving the world a glimpse of the new heirs.

While the royal mom made the feat look effortless (she stepped out just 7 hours after the birth of Prince Louis in 2018!), she’s now admitting that it was “terrifying” in a revealing new interview on the Happy Mum, Happy Baby podcast, hosted by bestselling author Giovanna Fletcher.

“Yeah, slightly terrifying, slightly terrifying, I’m not going to lie,” Kate said of her post-baby appearance after the birth of Prince George in 2013.

“Everyone had been so supportive and both William and I were really conscious that this was something that everyone was excited about and, you know, we’re hugely grateful for the support that the public had shown us, and actually for us to be able to share that joy and appreciation with the public, I felt was really important. But equally it was coupled with a newborn baby, and inexperienced parents, and the uncertainty of what that held, so there were all sorts of mixed emotions,” she continued.

Kate Middleton and Prince William introduce Prince George on the steps of St. Mary's Hospital

Kate, who is promoting her groundbreaking survey called “5 Big Questions on the Under Fives” on behalf of her focus on early childhood development, also recalled the first moment she held George in her arms.

“Amazing, amazing. It is extraordinary as I’ve said. How can the human body do that? It is utterly extraordinary actually,” she shared. “And he was very sweet. And I was also sort of relieved that he was a happy, healthy boy.”

Kate Middleton, Prince William and baby Prince George
| Credit: Scott Heavey/Getty
Kate Middleton
| Credit: Anwar Hussein/Getty

She also revealed that she and husband Prince William decided not to find out the sex of the baby before the birth.

“I didn’t know, no it was a surprise. But also seeing… you know your husband, William, and things like that. Seeing the pure joy of his face it was really special,” she said.

While she kept her royal composure on the hospital steps the next day, Kate admits that she had a hard first night after the birth of her first child.

“Everything goes in a bit of a blur. I think, yeah I did stay in hospital overnight, I remember it was one of the hottest days and night with huge thunderstorms so I didn’t get a huge amount of sleep, but George did, which was really great,” she shared. “I was keen to get home because, for me, being in hospital, I had all the memories of being in hospital because of being sick [with acute morning sickness] so it wasn’t a place I wanted to hang around in. So, I was really desperate to get home and get back to normality.”

The Duchess of Cambridge, Giovanna Fletcher
Kate Middleton and Giovanna Fletcher
| Credit: Kensington Palace

As for the famous moment when William put little George’s carseat in the backseat of their car, Kate admits it wasn’t as smooth as it seemed.

“We were like ‘What do we do?… in a swaddle?’ ‘How’s this supposed to work?’ We’d even tried to practice with a little baby, like a little doll, at home but you know it just never works out the way you planned it so it was quite hard to do that on the world’s stage, but no, he did a very good job,” she said.

Prince William
| Credit: Anwar Hussein/WireImage

She also admits that she “underestimated” how much their lives would change after they brought George home for the first time.

“Particularly with your first-born baby, you think everything is going to go back to how it was,” she shared. “I totally underestimated the impact and the change it had on our lives from that moment really and I think, unless you’ve got children, you don’t realize. No amount of planning and preparation can get you ready for that moment.”

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“It wasn’t that quiet in our household!” she told Fletcher. “William was like ‘Oh my gosh is this what parenting is going to be like?’

“It took us a bit of time to get ourselves settled and going again but that’s the beauty, I suppose, of having a newborn baby. You are pulled to your toughest and most unknown places that you hadn’t necessarily even thought about before.”