I read that as “So how do you think being child-free relates to rationality? Happiness?”, which would be understood as “So how do you think being child-free relates to rationality? How do you think it relates to happiness?”
I read that as “So how do you think being child-free relates to rationality? Happiness?”, which would be understood as “So how do you think being child-free relates to rationality? How do you think it relates to happiness?”