“And just like that, our hearts exploded into all of eternity and beyond ❤️🌈❤️” she captioned it. “Welcome to the world you little angel! ❤️Callum Michael Rebel Kazee 3/6/20."
Jenna’s fiance, Steve Kazee, posted a tribute of his own, as well as a snap of an adorable tiny hand.
"In an instant our universe burst wide open and nothing would ever be the same," he wrote on IG. "Welcome to earth star child."
The couple first announced they were expecting back in September 2019, releasing a joint statement that said: “We are beyond overjoyed and couldn’t be happier to be expanding our family!”
Jenna also has a six-year-old daughter, Everly, who she shares with ex-husband Channing Tatum.