Bey's sister, Solange, took to Twitter to confirm that she was a new aunt but said not all reports surrounding the birth are factual. "The most beautiful girl in the world," Solange wrote. "Information that goes through the telephone, always gets delivered wrong."
Jay's protégé and collaborator Rihanna also had some love for the new baby. "Welcome to the world princess Carter!" she tweeted, signing off: "Love Aunty Rih."
One of B's besties, Gwyneth Paltrow, wrote, "Welcome to the world Blue! We love you already."
The hip-hop community also celebrated the birth of Jay-Z's new addition. Fellow hip-hop mogul Russell Simmons tweeted, "congrats to my good friends Beyonce and Jay-Z." A few tweets later, he added, "today is the day the lord has made."
"Congrats to jay and B! God Bless :) !" Diddy tweeted. "And many more!"
Young Jeezy also shared his love for the twosome. "Congratulations to Jay-Z & Beyonce on baby Ivy Blue being born." (There has been some confusion about the order of the baby's first and middle names, with some outlets reporting it to be Ivy Blue instead of Blue Ivy.)
One of MTV's very own, "Jersey Shore" star Snooki, wanted to get in on the Beyoncé/Jay-Z baby party early Sunday. "Beyonce congrats on your baby gurl mama!!!!" she wrote. "So happy for you , you deserve it sexpot."
Mama-to-be Kourtney Kardashian added, "Congratulations to Beyonce, the 2nd Princess of Pop (behind Britney) for her new baby girl Ivy Blue!"
In the days leading up to the arrival, Beyoncé's pal Lady Gaga gushed about her mama skills. "Of course she is [going to be a good mom]," she said. "That's a tremendous understatement. She's the nicest female I've met in the industry. She's wonderful!"
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