Ring the alarm: The Carter twins are here. 

Though Beyoncé and Jay Z have yet to publicly announce the official expansion of their family, the singer's father, Mathew Knowles, took to Twitter on Sunday morning to congratulate his daughter.

"They're here!" Knowles wrote, along with an image of balloons and a sign reading, "Happy Birthday to the twins! Love, Granddad."

Numerous celebrity sites had reported the news earlier, citing unnamed sources.

“Bey and Jay are thrilled and have started sharing the news with their family and closest friends,” a source told People. On Saturday, E! News reported a Jay Z and Blue Ivy sighting at Los Angeles-area hospital. 

The Beyhive has been swarming with rumors for weeks. Speculation grew when Escalades that headed to UCLA Children’s Hospital were spotted leaving the couple’s neighborhood on June 13. Beyoncé, typically active on Instagram, hadn’t posted since May 30, leaving many fans to wonder if her absence marked the arrival of the twins. 

Beyoncé first announced her pregnancy on Instagram in early February, and her yet-to-be-born babies quickly became the subjects of the social media platform’s most-liked post ever, garnering more than 7.2 million likes in less than 24 hours. 

Beyoncé and Jay Z are also parents to 5-year-old Blue Ivy.