Jenna and Barbara, who are about to release their upcoming children's book, The Superpower Sisterhood, are extremely close and Jenna shared that when she got the phone call she "started bawling" before remembering that it was "not helpful" and she wneeded to "stay calm".
WATCH: Jenna Bush Hager praises mom Laura Bush after sharing emotional story about daughters
"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 mom-of-three told People.
"But she was, of course, prepared because I think she has all the love to give."
Barbara and husband Craig Coyne welcomed their first daughter, Cora Georgia, on 27 September 2021, but she gave birth in Maine instead of the planned hospital in New York.
Barbara also shared the poignant moment that she realized she had given birth in the hospital that was named after her late grandmother, whom Barbara was also named after.
The twins are very close
"I went there to visit [Cora, who remained in NICU] and looked over on the wall, and it said Barbara Bush Children's Hospital," Barbara shared.
"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."
Cora stayed in the NICU for four weeks. "She just needed some help figuring out the basics like breathing and getting stronger to be able to do those things on her own," added her mom.
Jenna took to social media
Jenna shares daughters Margaret, eight, six-year-old Poppy Louise, and son Hal, two, with husband Henry Hager.
However the family has all contracted COVID-19 with Jenna taking to social media to share the news, posting a selfie and captioning it: "This is the face of a COVID+ mama. We are all isolating and feeling super grateful for the vaccine and my darling babes."
In the snap Jenna was make-up free and wearing a simple black sweater with her hair tied off her face.
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