Beyoncé celebrated the fourth birthday of her twins Rumi and Sir Carter on Sunday.

The multi-Grammy-winning singer wished her second daughter and her son happy birthday on her website.

"What's better than 1 gift... 2. Happy birthday Rumi & Sir," the message read.

Beyoncé and her husband, Jay-Z, welcomed Rumi and Sir Carter on June 13, 2017. The couple also share nine-year-old Blue Ivy, who became the second-youngest person to win a Grammy Award for her contributions to "Brown Skin Girl."

"Something cracked open inside of me right after giving birth to my first daughter," Beyoncé told Vogue in a cover story last November. "From that point on, I truly understood my power, and motherhood has been my biggest inspiration. It became my mission to make sure she lived in a world where she feels truly seen and valued."

Beyoncé said she was "deeply inspired" to amplify Black and African voices with her film Black Is Kingafter a family trip to South Africa.

"After having my son, Sir Carter, I felt it was important to uplift and praise our boys and to assure that they grow up with enough films, children's books and music that promote emotional intelligence, self-value and our rich history," she noted. "That's why the film is dedicated to him."

Happy birthday, Rumi and Sir!

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