Prince William recently jetted off to Vietnam [1] for a quick two-day tour, and while he's probably nursing some jet lag at home, his wife, Kate Middleton, has been hitting the town on her own. After spending the day painting dinosaur eggs with schoolchildren [2] at the Natural Museum of History in London on Tuesday, the duchess of Cambridge attended the Place2Be Wellbeing in Schools Awards at the Mansion House. Dressed in a gorgeous black dress [3], Kate showed off her sporty muscles [4] as she chatted with fellow guests before giving a speech [5] on stage. The event is very close to Kate's heart, as it raises funds to encourage positive mental health in schools [6]. But the standout moment of the night came when an adorable little baby stuck his tongue out at Kate. Since babies do that all the time (and he probably had no idea he was in the presence of royalty), it's more hilarious than anything else. See more of her fun night ahead.