A possible confounding variable in the attachment style/happines dichotomy is whether the child was bullied in school. A securely attached child may become an insecuraly attached young adult after a traumatic experience in school. In addition, some other possible explanations for an individual's well being later in life include whether the individual has experienced another form of emotional trauma, such as--as the textbook suggests--the loss of a parent.
I agree to some extent with this statement. However, most of the time, the children who are bullied are not securely attached children. Bullies usually pick on children who lack self-confidence, which is more a characteristic of the other attachment styles.
I would agree that so much of children's security is the way they feel at school. It is a time when they are away from their mother and if they are not secure, they might not cope well. Also being at school is the best test if a child is secure because if they can exist fine at school then they can prove that they can exist in the real world without their mother and still be fine. But kids that are subject to bullying and things of that nature, kids might respond differently to the bullying if they are secure themselves or not, another test of if they are truly secure or not.
