Popsugar Celebrity The Royals Prince William and Kate Middleton Talk About Baby Sussex LOL! Will Welcomes Harry to "the Sleep Deprivation Society" After Baby Sussex's Birth 7 May 2019 by Kelsie Gibson Image Source: Getty / WPA Pool You can always count on Prince William for a good dad joke. On Tuesday, the royal and his wife, Kate Middleton, attended the launch of The King's Cup Regatta in London and took a moment to talk with the press about the arrival of Prince Harry and Meghan Markle's first child. While they said they are "absolutely thrilled" about the birth of baby Sussex, Will couldn't help but poke a little fun at his younger brother. "I'm very pleased to welcome my brother to the sleep deprivation society that is parenting!" he teased. All jokes aside, Kate also gave her best wishes to the first-time parents. "It's really exciting for both of them," she said. "These next few weeks, it's always very daunting first time around, so wish them all the best." She also added that she's excited to have another Spring birthday in the royal family — her son Prince Louis's birthday is April 23, while her daughter, Princess Charlotte, just turned 4 on May 2. "It's such a special time — with Louis and Charlotte just having had their birthdays. It's such a great time of the year to have a baby. Spring's in the air, so it's really great," she said. "As William said, look forward to meeting him and finding out what his name's going to be." See more photos from their latest appearance ahead! Related: Everything You Need to Know About Meghan and Harry's Baby, in 1 Handy Place "We're absolutely thrilled - welcome to the Sleep Deprivation Society!" — The Duke of Cambridge on his and The Duchess's delight at the birth of The Duke and Duchess of Sussex's son pic.twitter.com/3sTvDL14Cr— Kensington Palace (@KensingtonRoyal) May 7, 2019 1 / 15 VIDEO: William & Kate say they look forward to meeting #babysussex. Wills: “We’re absolutely thrilled & look forward to seeing them in the next few days... I’m v pleased to welcome my brother to the sleep deprivation society that is parenting!” pic.twitter.com/W6ldWWsUgn— Emily Andrews (@byEmilyAndrews) May 7, 2019 2 / 15 Image Source: Getty / WPA Pool 3 / 15 Image Source: Getty / WPA Pool 4 / 15 Image Source: Getty / WPA Pool 5 / 15 Image Source: Getty / WPA Pool 6 / 15 Image Source: Getty / WPA Pool 7 / 15 Image Source: Getty / WPA Pool 8 / 15 Image Source: Getty / WPA Pool 9 / 15 Image Source: Getty / WPA Pool 10 / 15 Image Source: Getty / WPA Pool 11 / 15 Image Source: Getty / Neil Mockford 12 / 15 Image Source: Getty / Samir Hussein 13 / 15 Image Source: Getty / Samir Hussein 14 / 15 Image Source: Getty / WPA Pool 15 / 15 The RoyalsThe British RoyalsRoyal BabyPrince WilliamKate Middleton