jenna bush/ instagram
Documented on Instagram by Jenna, the sisters can be seen taking part in what appears to be a family gathering that includes the Today co-host's three children, Margaret "Mila" Laura, 8, Poppy Louise, 6, and Henry "Hal" Harold, 2, as well as Barbara's infant daughter, Cora Georgia, 1 month.
"Happiest birthday to my dearest, partner-in-all, the girl with the giant heart, kindest soul. The best gift of my life is being your sister," Jenna wrote alongside the series of pics. "And this year, the most precious is having our babes fall in love."
"I don't know what I did in a past life but having you as a sister is pure magic," she added. "@barbara.p.bush you're a dream."
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Barbara previously welcomed Cora on Sept. 27, her parents, George and Laura, both 75, previously announced.
In an Instagram post shared days later, Jenna revealed the first photos of her twin sister's newborn baby alongside a sweet tribute to the little girl.
One image featured Jenna gazing lovingly at the mother-daughter duo, while another picture showed Barbara and her husband, Craig Coyne, cozying up with the newest addition to their family.
Jenna also posted two snapshots of herself holding the infant in her arms.
"Dearest Cora Georgia, Today is the day I got to meet my most beautiful, precious, feisty, niece (a bit earlier than we expected!)," wrote Jenna. "I witnessed in awe as my dearest, toughest @barbara.p.bush became a mama. And today is the day I fell in love! Some cousins are anxiously waiting to play with you, but not just yet love. Xx auntie j."