Jenna Bush Hager on Feeling 'Guilt' Over 3rd Pregnancy as Friends Struggled to Expand Families (Exclusive)

ET spoke with the 'Today' show co-host and author about her new book, 'Everything Beautiful in Its Time.'

Jenna Bush Hager is getting candid about the "guilt" she felt after discovering she was pregnant with her third child, as her friends struggled to expand their families. In 2019, the 38-year-old former first daughter and author had been hired to replace Kathie Lee Gifford on the Today show. But at the time, she felt guilty about her news as her co-host, Hoda Kotb, was looking to adopt another baby.

"I almost felt guilty because it was so much at once. I found out I was pregnant, I also had gotten this job. I knew from Hoda that she was dying to have another little girl to give Haley a sister. She told me that months before," the co-host of Today With Hoda & Jenna tells ET's Rachel Smith while promoting her new book, Everything Beautiful in Its Time: Seasons of Love and Loss. "We weren't really trying to have a baby. We got pregnant and I called my mom and I said, 'I just have to tell her. I feel bad for a lot of people that are struggling and then I just get pregnant.'"

"I went and I sat across from Hoda and I told her, and she wept with tears of joy for me," she recalls. "Not long after she got her baby."

Bush Hager shares daughters Margaret, 7, and Poppy, 4, with husband Henry Hager. She gave birth to her third child, son Henry "Hal," on Aug. 2, 2019.

"My mom always says everybody gets their baby when they’re supposed to," the mother of three relays. "And Hoda has a little girl and I had Hal after. So who knew, but just everything is supposed to happen when it’s supposed to happen."

Bush Hager writes all about the joys of motherhood and the pain of loss in her new book. Three of her beloved grandparents -- George H.W. Bush, Barbara Bush and Jenna Hawkins -- died over the course of one year.

"It’s a book about losing my three remaining grandparents. I lost them in a span of a year," explains Bush Hager, who said she got inspired by the bible verse Ecclesiastes 3:11. "Which basically says God makes everything beautiful in its time. I think when you’re dealing with love and loss, you can realize that one day time will heal and you’ll be thinking back on these people and missing them, but also just so grateful for their lives and for the fact that you got to have these relationships with them."

"These are raw moments of how much I loved them, but then also the moments of finding out they were gone. I write about that all," she explains, adding, "But I think I wrote about it for myself too, honestly, because it was cathartic. It was therapeutic to put my words, my grief onto paper."    

In the book, she also writes about how she enjoyed watching her daughters next to her grandparents, the last moments of their lives, and how it was a "really poignant thing as a mom because it was just this youth next to this wisdom."

And while she and twin sister Barbara made headlines for their partying days while their father, George W. Bush, was president, she learned many important lessons from her grandparents.

"When my dad became president, we weren't prepared for it. We made mistakes and we made them publicly," Bush Hager admits. "But I also am so grateful that I had parents and grandparents that allowed us to fail, because how could you possibly parent if you were expected to be some perfect version of yourself?"

Meanwhile, Bush Hager is all about looking on the bright side and "finding joy -- and choosing it."

Whether it was landing a new job and then getting pregnant amid losing her loved ones, she chose to "look at all these wonderful things as blessings, as something you’re grateful for."

"It helps every single day whether you’re going through grief or not," she notes.

Everything Beautiful in Its Time is out now.