09/21/2017 10:31 EDT | Updated 09/22/2017 14:43 EDT

The Duchess Of Cambridge's Due Date Might Be Earlier Than Expected

Prince William let slip a little clue about when Kate might give birth.

Max Mumby/Indigo via Getty Images
Catherine, Duchess of Cambridge visits the Sunken Garden in the grounds of Kensington Palace on August 30, 2017 in London, England. The Sunken Garden has been transformed into a White Garden dedicated to Diana, Princess of Wales mother of The Duke of Cambridge and Prince Harry marking the 20th anniversary of her death. (Photo by Max Mumby/Indigo/Getty Images)

The world might be greeting a little prince or princess sooner than expected!

When Kensington Palace announced on Sept. 4 that the Duchess of Cambridge and Prince William were expecting their third child, it was assumed that the future royal baby would be born sometime in April 2018, based on the assumption that Kate was around three months pregnant.

However, Will let slip a clue that the duchess' due date is earlier than we thought.

Pool/Samir Hussein via Getty Images
Prince George of Cambridge, Prince William, Duke of Cambridge, Catherine, Duchess of Cambridge and Princess Charlotte of Cambridge depart from Hamburg airport on the last day of their official visit to Poland and Germany on July 21, 2017 in Hamburg, Germany. (Photo by Pool/Samir Hussein/WireImage)

On Sept. 19, the prince visited a charity centre in London called Spitalfields Crypt Trust, and while chatting with the staff, a midwife congratulated him on Kate's pregnancy. William replied by saying, "All the best with the midwifery. I may see you sooner than you think."

Now, it's very possible that William was just making a joke, implying that time will fly by between now and Kate's due date. It's also possible that the Royal Family decided to hold off on the announcement longer than the usual three months.

After all, in their announcement the Palace stated that Kate had to miss some of her royal engagements because she was suffering from hyperemesis gravidarum (HG), a severe type of morning sickness that can cause severe nausea, vomiting, weight loss, and even a hospital stay.

And William himself previously said that his wife's pregnancy was "a bit anxious to start with."

Kate, who is mother to Prince George, 4, and Princess Charlotte, 2, suffered from HG in her previous two pregnancies, and although she has stayed mum on the topic, other moms who have experienced the same have opened up about what they went through.

Mike Marsland via Getty Images
Prince William, Duke of Cambridge and Catherine, Duchess Of Cambridge depart the Lindo Wing with their new baby daughter at St Mary's Hospital on May 2, 2015 in London, England. The Duchess was safely delivered of a daughter at 8:34am this morning weighing 8lbs 3oz. (Photo by Mike Marsland/WireImage)

"Like Kate, I also suffered from HG during each of my pregnancies; and it wasn't just uncomfortable, it was downright terrifying," mom Sarah Bregel wrote in Babble. "In the worst of it, which lasted with both pregnancies until about 16 weeks (when medication finally took effect and allowed me to usually keep down food and water), I could barely lift my head from a pillow or sip water without vomiting it right back up."

Like Kate, I also suffered from HG during each of my pregnancies; and it wasn't just uncomfortable, it was downright terrifying.

Fortunately, it seems like Middleton is starting to recuperate, as the Palace announced that she will be making her first public appearance since the pregnancy announcement on World Mental Health Day, Oct. 10.

Earlier this week, the duchess appeared in a video — filmed before the pregnancy news — for the Anna Freud National Centre for Children and Families, in which she encouraged children to open up about their feelings and stated, "You're never too young to talk about mental health."

We hope the duchess starts feeling better soon!

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