E! NEWS EXCLUSIVE: Guess Which Twin Was First! Rumi and Sir Carter's Birth Details Revealed MUST CREDIT E! NEWS AND LINK BACK TO: http://www.eonline.com/news/867562/guess-which-twin-was-first-rumi-and-sir-carter-s-birth-details-revealed Rumi Carter will always have bragging rights over her little brother. That's right—Beyoncé's newborn daughter was first to be born, E! News has learned. However, while Rumi arrived at 5:13 a.m., Sir Carter also made it into the world before the clock struck another minute. As for their mysterious birth date, E! can confirm they were born on June 13, 2017. Unlike their famous parents and big sister Blue Ivy Carter, who all have middle names, the newest members of the Carter family only have first and last names, so those "Sir Carter Carter" rumors can be put to rest. Their Grammy-winning mama first raised questions about their middle names when she shared their first photo online a month after the birth. "Sir Carter and Rumi 1 month today," Beyoncé captioned the shot that immediately broke the Internet. It didn't take long for fans to wonder about Bey's caption and whether or not Carter appeared in Sir's name twice. Logistics aside, the Carter family is clearly thrilled about their new bundles, including Blue. As an insider told E! News, the 5-year-old is loving the babies and being a big sister. The source said that she helps Beyoncé take care of the little ones and, despite all the attention being paid to the twins, Beyoncé and Jay-Z are making sure to give a lot of love to their oldest and play with her often. From the sound of it, they're all crazy in love with the little ones! #june13th #cartertwins #nomiddlenames #babyfever #caterchildren special thanks @e_tv_pr with @eentertainment watch @enews #nbcuni #katiemoeckel