Jenna Bush Hager Remembers Last-Minute Target Run for Diapers After Sister Barbara's Baby Came Early

Jenna and Barbara Bush
Jenna and Barbara Bush

Nathan R. Congleton Jenna Bush Hager and Barbara Pierce Bush

When Jenna Bush Hager got a late-night text that her twin sister Barbara Pierce Bush had gone into labor almost six weeks early, she called Barbara's husband Craig Coyne and burst into tears.

"I started bawling. I was like, 'Wait, wait, wait. This is not helpful. I'm supposed to stay calm,' " Jenna tells PEOPLE during a joint interview with Barbara about their upcoming children's book, The Superpower Sisterhood.

"Of course, I was nervous for her and knew that she was unprepared physically — meaning she didn't have the diapers or the nursery set up," the Today with Hoda and Jenna co-host, 40, continues. "But she was, of course, prepared because I think she has all the love to give."

On Sept. 27, 2021, Barbara welcomed her first baby, Cora Georgia, with Coyne in Portland, Maine instead of New York as they'd planned. Barbara says that the experience was "incredible." What made Cora's birth even more special was that she stayed at the neonatal intensive care unit (NICU) at a hospital in Portland named after Barbara's late grandmother, former First Lady Barbara Bush, who passed away in 2018.

"I went there to go visit her and looked over on the wall, and it said Barbara Bush Children's Hospital," Barbara, 40, remembers. "So, in many ways, it felt divine that she was born in Maine near where we were married and where we have so many memories as a family. Then I felt how poignant and meaningful it was in a place that meant something to my grandmother."

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Barbara Bush with daughter Cora Georgia Coyne
Barbara Bush with daughter Cora Georgia Coyne

Laura Foote Barbara Pierce Bush with her daughter Cora

RELATED: Barbara Bush Reveals Daughter Spent Time in NICU Named After Her Grandmother: 'It Felt Divine'

While Barbara and Coyne got acquainted with their new baby, Jenna was quick to hop on a flight and help get all the baby gear they'd need.

"The next day after Cora was born, Jenna flew to Maine and helped us, she went to Target and did a big run," remembers Barbara, the CEO and co-founder of Global Health Corps. "We didn't have a thing. We just weren't expecting it. We didn't have a car seat to bring her home from the hospital in or any of the necessities one needs with a baby."

Since baby Cora was born premature, she ended up staying in the NICU for about four weeks, her mom says. "She was premature and very healthy," says Barbara. "She just needed some help figuring out the basics like breathing and getting stronger to be able to do those things on her own."

That didn't stop Cora's Aunt Jenna from showering her with love. After her visit to Target, Jenna says she got to cuddle with her baby niece.

"I got to hold [and] meet the baby and see Barbara through totally different eyes," says Jenna. "She hasn't needed any advice. But I think watching her fall in love — and now I get to have a baby niece — is so much fun."

Bush Family
Bush Family

John Unrue From left: Henry Hager, Mila, Hal, Jenna, George W., Poppy, Laura, Barbara, baby Cora and Craig Coyne in a recent family photo.

The twin daughters of former President George W. Bush and former First Lady Laura Bush have always been a team. They celebrated their strong bond in their bestseller, Sisters First. It was while on that book tour that Jenna and Barbara came up with the idea for their latest book, The Superpower Sisterhood, which will be released by Little, Brown Books for Young Readers on April 19.

"There were so many people that said, 'Gosh, I wish I had a sister, like you and Barbara [have],' " Jenna says. "It reminded us a lot of our mom, who was an only child, and that sisterhood comes in so many different ways."

The Superpower Sisterhood follows a young girl named Emma, who makes friends with two sets of sisters who move to her neighborhood. They quickly realize the power they have when they bring their unique set of talents together.

Barbara and Jenna hope their own girls will have equally powerful friendships and dedicated the book to them. (Jenna shares daughters Mila, 8, and Poppy, 6, and son Hal, 2, with husband Henry Hager.)

superpower sisterhood
superpower sisterhood

"To our daughters — may you use your powers to empower others," they wrote.

Even though their children are all different ages, the authors are already seeing a special connection form between them — one they've always hoped for.

"My kids are totally obsessed [with Cora]," says Jenna. "To watch them fall in love with this baby has been the most beautiful gift. Hal's only 2, but he prays for baby Cora every single night."

She adds, "I think that's what Barbara and I envisioned as little girls in some ways. To watch it come true is so special."

The Superpower Sisterhood goes on sale April 19.