Their photos show that the adorable tot is walking! He went around the exhibition and pointed out interesting things that caught his attention! He was clad in a snuggly navy jacket, matching trousers and little Nike running shoes.
The one-year-old captured people's hearts with his cuteness with many fans taking to social media to remark about how sweet he is and how big he is getting.
Unfortunately, Louis wouldn't have been able to see the Natural History Museum's iconic Dippy the Dinosaur. The behemoth Diplodocus cast is touring the UK until Oct. 31.
There were still plenty of things at which Louis and Maria could marvel, such as a dinosaur fossil trail. It includes the skull of a Triceratops and part of the first Tyrannosaurus rex skeleton ever discovered!
Royals fans last saw Louis was during the Queen's annual Christmas lunch at Buckingham Palace. The Cambridge family was photographed arriving and leaving the event, and people were floored by how much Louis looked like his older brother.
Kate was not with Louis this week because she was busy with multiple royal engagements. She embarked on a whirlwind 24-hour tour of the UK on Jan. 21 and 22 as part of the launch of "5 questions on the under 5s," a survey which gives parents the opportunity to share their needs and concerns about how to raise the next generation.
The busy duchess made a lightning fast trip around England and Wales. She started with a surprise visit to the Birmingham Science Museum on Jan. 21. The following day, she visited the Ely and Careau Children's Centre in Cardiff and then stopped by HMP Send in Woking, England. She was even "offered" a job during her royal engagement!