The co-parents put together an early Spider-Man-themed party for son Jace Joseph's 4th birthday which Kramer, 38, documented on Instagram Sunday.
"Happy almost 4th birthday my little Spidey," the mom of two captioned the photo on her Instagram Story, where she stands on one side with Caussin, 35, on the other and Jace and Spider-Man standing in the middle.
On Monday, she shared more scenes from the party, writing, "About yesterday ❤️."
"Jace's birthday is tomorrow so had to throw him the ultimate Spiderman birthday!!! He had the best time and was legit starstruck when Spiderman walked through the door 😅🎉 Can't believe this little man is about to be 4!"
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Recently appearing on Facebook Watch series Red Table Talk in a conversation about toxic forgiveness, Kramer said she became resentful of the infidelities in her relationship and what divorce would mean for her family. She recalled thinking, "You don't get to do what you did and take my child away from me."
"I became real big mama bear," she recalled, later reflecting on where she's at today and noting, "I know we're both in better situations. But I think about this year ... my kids won't wake up at my house Christmas day. That one's gonna hurt."
"That's when I get like, that's not fair. You took away my dream too, of what I wanted for my family," she said. "That's not fair."
Rich Fury/Getty Jana Kramer and Mike Caussin
Kramer added, "Even now, as long as we don't talk about us and our relationship, we're great."
"You know what I mean? We got divorced for a reason," she added.
When Zampino noted that she and ex-husband Will Smith "are better as co-parents than we were at husband and wife," Kramer nodded, adding, "that's how it's shaping up to be with me and my ex."