Just that they identify one secure attachment style - corresponding to happy families are all alike - but the ways we DON'T attach are different. It was really interesting for me to read Wallin on attachment. They ie John Bowlby started out with a smaller number of insecure attachment styles, and have gradually identified a couple more. I mean, this is one part of psychology where a woman got involved and said lets actually watch women with their babies - it wasnt all Freud writing stuff out of his head in his office on coke - not to be disrespectful or anything