Atlee entered the world on May 8 and is the third child for the 26-year-old, who is the daughter of politician Sarah Palin. Bristol also has a 1-year-old daughter, Sailor, with husband Dakota Meyer and shares an 8-year-old son, Tripp, with her ex, Levi Johnston.
Bristol later shared a cute photo of the newborn wearing a custom embroidered nightgown, followed by a snap featuring Dakota holding Atlee, clad in a "Daddy's princess has arrived" outfit.
The former reality star recently blogged about her latest addition, saying that Dakota did "amazing" during the "breeze" birth.
"[Dakota] held my hand, took care and encouraged me the entire time," she wrote. "I could not have a more supportive husband. This pregnancy has strengthened our bond and made our relationship stand even firmer on the foundation that we have proudly built up for our little family.”
A new bundle of joy isn't the only change for Bristol and Dakota -- the couple, who are about to celebrate their first wedding anniversary, recently relocated to Texas.
"When Dakota and I got married, we both agreed that we would 'meet in the middle' and move somewhere to dig our roots in a mutual, new, place," Bristol said. "We decided on Texas, and I couldn't be happier! The kids love it too. I feel like my life has never been this 'normal.'"
For more on Bristol and her family, watch the video below.