The new parents announced the birth of Daisy Dove in a statement issued via UNICEF chiefs in the early hours of Thursday (27Aug20), sharing a close-up black-and-white photo of Katy and Orlando holding the tiny tot's hand on each of their social media accounts.
They were immediately showered with well wishes from followers, including the "Pirates of the Caribbean" actor's former wife, Miranda, with whom he shares nine-year-old son Flynn.
"I'm so happy for you guys," she commented on Katy's post. "Can't wait to meet her."
The Australian beauty, who divorced Orlando in 2013 after three years of marriage, also 'liked' the Brit's identical post.
She is now married to Snapchat co-founder Evan Spiegel, the father of her two younger sons, Hart, two, and Myles, 10 months.
Meanwhile, former U.S. First Lady and Secretary of State Hillary Clinton also offered her congratulations, adding, "Wishing you and your new family all the joy in the world."
"I am sooo happy for youuuu (sic)," posted singer Noah Cyrus, while Katy's fellow "American Idol" judge, Lionel Richie, tweeted, "Congratulations @KatyPerry, being a parent is one of the greatest joys life can bring! I'm so excited for you and Orlando to begin this journey! Wishing you both and #BabyCat all the best. Lots of love, Uncle Lionel!"
Comments were also left on Orlando's Instagram announcement from fellow actor Luke Evans, "Stranger Things" star Millie Bobby Brown, and good pal Justin Theroux, who remarked, "DAISSSSYYYY (sic) !!!!! WELCOME!!!! and Love to both Mama and Papa."