The two newest additions to Beyonce and Jay Z's family have been revealed.
On July 13, the first official photo of Beyonce with her newborn twins was shared on Instagram, reports the Daily Mail, though Jay Z was notably absent.
In the post, Beyonce confirmed the unusual names of the baby girl and boy: "Sir Carter and Rumi 1 month today," she wrote, accompanied by a picture of the infants resting comfortably in her arms.
As reported in June by TMZ, the company run by Beyonce and Jay Z trademarked the names, as was done earlier in the year for their 5-year-old daughter, Blue Ivy.
TMZ speculated that the name "Rumi" is a reference to the 13th century Persian poet Jelaluddin Rumi. It is also a Japanese girls' name, notes the Daily Mail. "Sir Carter" refers to Jay Z's real name, Shawn Corey Carter.
When Beyonce's pregnancy was announced January with a picture of the mother-to-be kneeling in front of a huge wreath of flowers wearing just a bra, underwear and a veil, it quickly became the most liked post on Instagram.
The accompanying caption said: "We would like to share our love and happiness. We have been blessed two times over. We are incredibly grateful that our family will be growing by two, and we thank you for your well wishes."
Before the birth of Blue Ivy five years ago, Beyonce suffered a miscarriage, which she first revealed in her 2013 HBO documentary, "Life Is But a Dream."
"About two years ago, I was pregnant for the first time," she explained. "And I heard the heartbeat, which was the most beautiful music I ever heard in my life. I picked out names. I envisioned what my child would look like…. I was feeling very maternal."
However, she lost the child in the early stages of her pregnancy.
"I flew back to New York to get my check up -- and no heartbeat," she said. "Literally the week before I went to the doctor, everything was fine, but there was no heartbeat."
In the documentary, she went on to explain that writing songs about the experience served as therapy, helping her cope with the devastating loss.
The arrival of Sir Carter and Rumi coincides with the release of Jay Z's new album, "4:44."
The title track features an apology from him to Beyonce, leading to speculation that it's a specific response to lyrics about "Becky with the good hair" on her album "Lemonade."