Blue Ivy is the "best big sister" with twins Rumi and Sir Carter, says a source
“Blue is the best big sister,” says the source. “[She] helps Beyoncé every day.
“Everyone is doing great,” adds the source. “They are still enjoying the summer in Malibu. Blue is excited to be back in school soon. The babies are growing and very cute.”
JAY-Z and Beyoncé welcomed their twins on June 13, according to birth certificates obtained by PEOPLE.
The parents quickly filed papers to trademark the apparent monikers for everything from fragrances and cosmetics to baby gear, tote bags, and water bottles.
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The family is currently living in a $400,000 per month rental home in the beach city, while looking for a permanent home closer to Blue’s school.