Jenna welcomed her second child — her first with fiancé Steve Kazee — on March 6, 2020. As a nod to his dad's middle name, Callum's first middle name is Michael. After his birth, Jenna said her baby boy exploded her heart "into all of eternity and beyond."
Steve gushed about his little one after taking photos to mark his turning 5 months old, saying: "Time is flying by so fast that this picture is already two weeks old. This little human hit 5 months old on August 6th and I can't even believe it. In the first few months of this little monkey being on this earth I have laughed harder than I've ever laughed, I've worried more than I have ever worried, I've cried harder than I've ever cried, but most of all I have loved more than I've ever loved. All thanks to you Callum. Love you bub!"
On Callum's first birthday, both Jenna and Steve shared photos with sweet captions in honor of their son. "The fact that this little angel baby is one years old today is blowing my mind," Jenna captioned her photo. "Callum, you came in to this world and changed it the instant you were here . . . you brought with you pure joy, pure love and a little spark of the divine that i have a feeling will never leave. You bring everyone around you together like the bright shining sun and we all want to bask in it all day. It is an absolute gift and honor to be your mommy. . . we love you beyond our little rainbow baby!!!"
Steve wrote on his own account: "This is 1!! Well it was one hell of a year. I don't what we would have done without you bub. Every day I wake up and thank the stars that they sent you to us. What an absolute blessing. Your smiles light up the darkest of days and your eyes hold in them all the love we ever need to keep going. The best child and the best sibling that we could have ever wished for you. Here's to many more years to share! Love you star baby!"