Yes, there are two very revealing bits of dialog in the novel. During the week before the Great Massacre of 1955, "...There was only one annoying complication. Connie and Carlo's oldest boy was to receive his Confirmation in the Catholic Church and Kay asked Michael to be the Godfather. Michael refused. 'I don't often beg you,' Kay said. 'Please do this just for me. Connie wants it so much. And so does Carlo. It's very important to them...'" Michael finally agrees, but says he can't leave the mall (presumably for security reasons), so the Confirmation had to be held in the Mall. Later, after Connie's hysterical accusation, Kay split with the kids for New Hampshire and Hagen came calling to get her to return. Kay knows Michael was behind Carlo's murder (and Tessio's), but Hagen says to her, "You've got Michael wrong. You're mad because he lied to you. Well, he warned you never to ask him about business. You're made because he was Godfather to Carlo's boy. But you made him do that."
These very revealing bits of dialog in the novel imply a couple of things. First, it may have been Kay's idea, not Connie's, for Michael to be godfather to Connie's boy. Sure, Connie wanted it, but Kay may have initiated the idea. The second bit of dialog in New Hampshire suggests another Michael Corleone quid pro quo: it's your fault for not listening to me. Do it my way or no way. In the film, Michael stands godfather to a newborn at his baptism, which is very cold-hearted and calculating (and gives us a dramatic contrast: total innocence vs. evil murders). Michael agreed in order to create an alibi. But the novel builds a moral "out" for Michael: it's for an older boy (who conveniently turns into a thief in GFII), at his Confirmation, not Baptism, and Michael was more concerned with security than creating an alibi.