Kate Middleton and sister Pippa Middleton have the shared experience of having children, but the siblings had very different pregnancies. While the Duchess of Cambridge suffered with extreme morning sickness, also known as hyperemesis gravidarum, her sister was lucky enough to have no sickness symptoms.
GALLERY: 12 most beautiful royal pregnancy photos of all time – from Duchess Kate to Princess Diana
While Pippa mainly stays out of the limelight, she did mention her first pregnancy while writing a column for Waitrose magazine, which is where she revealed her lucky escape. She penned: "I was lucky to pass the 12-week scan without suffering from morning sickness. That meant I was able to carry on as normal".
WATCH: Giving birth at the Lindo Wing is exactly how you'd expect
Kate wasn't as fortunate as her younger sister. It is documented that the Duchess suffered with feeling unwell through all three of her pregnancies, but it was so severe when she was pregnant for the first time with Prince George that the royal was even admitted to hospital.
MORE: Relatable Kate! All the times the Duchess has spoken candidly about parenting struggles
MORE: The Queen's birth stories of her children Charles, Anne, Andrew and Edward
Kate struggled with her pregnancies due to a rare condition
When unable to keep anything down, a hospital stay will allow any fluids to be administered via a drip to keep mother and baby hydrated and healthy.
Speaking out about her birth experience on Giovanna Fletcher's Happy Mum, Happy Baby podcast, Kate admitted it had been "terrifying" to give birth to her first child, George.
With the world's press waiting outside of the Lindo Wing at St. Mary's hospital in London for any news, Giovanna asked Kate to thick back to that day to express how she felt.
The Duchess has made candid comments about her first labour
"It was slightly terrifying, I'm not going to lie. Everyone had been so supportive and both William and I were conscious that this was something that everyone was excited about, and we are hugely grateful for the support that the public has shown us, and actually for us to share that joy and appreciation with the public was equally important.
"But equally, it was coupled with a newborn baby and inexperienced parents and the uncertainty about what that held. So there were all sorts of mixed emotions."
Make sure you never miss a ROYAL story! Sign up to our newsletter to get all of our celebrity, royal and lifestyle news delivered directly to your inbox.