The Duchess has juggled life as a working royal with raising her brood.
She undertakes royal duties, overseas tours and has recently taken part in video streams, TV programmes and podcasts.
Thankfully, this privileged mum has lots of help on hand to tackle both important roles.
However, Kate has still told fans of feelings of guilt and questioning herself affect her, even while enjoying the help that comes with being a royal mum.
She went on: “There’s such a pull, but I am such a hands-on mum, and whatever you’re doing you want to make sure you’re doing the uttermost best job you can for your children.”
“But no, it’s a constant challenge, you hear it time and time again from mums.
“Even mums who aren’t necessarily working, aren’t pulled in the directions of having to juggle work life and family life – there’s always something.
“And always sort of questioning your own decisions, and your own judgments, and things like that, and I think that starts from the moment you have a baby.”
However, there are some signs fans could expect from Prince William to indicate a pregnancy.
Body language expert Judi James told Express.co.uk: “William would be a very poor poked player as his facial expressions are often a give-away, especially when it comes to any good news.
“Unlike his dad he might manage to mask negatives like anger or frustration, but watch out for a lot of suppressed smiling if/when he is sitting on a fourth baby secret.
“Trying to suppress a smile leads to a softened eye expression and narrowing and crinkling of the eyes, plus a pushing together of the lips, but the smile breaking out at the corners.”