The 59-year-old actor shared the sweet moment with Carmen, his daughter with wife Hilaria Baldwin, before discussing his family with DeGeneres.
"Our son Rafael is 22 months, and we have a son, Leo, who is 7 months," Baldwin said of his other children with Hilaria. "So we have three kids in three years."
"I love having kids again. They're great," he added before revisiting moments from The Boss Baby premiere in March. "[Carmen is] is jumping up and down on the red carpet and posing for pictures. She's like Debbie Reynolds, she's performing ... [Rafael] is [smouldering]. He's James Franco."
"We're going to have [our third] and then we're going to enjoy them," the star said.
"We did pretty well with [the first] two. We looked at each other and go, 'How could one more of these be wrong?' We were happy to have another baby," he added. "I just can't describe what it means to me."
Baldwin will next star in Blind with Demi Moore, and is also slated for M:I 6 - Mission Impossible with Tom Cruise, The Public with Jena Malone and The Private Life of a Modern Woman with Sienna Miller.