I think the standard of living individually can affect both an infant's attachment and his/her higher well being later in life. Suppose, an infant's parents' have a low income, then that could affect the way they took care of the infant and thus his/her attachment. That might later also affect whether he/she went to school, etc. and thus a higher well being in later life. although income here would affect both affect the attachment and the higher well-being, the latter two might not have direct corelation.
Other factors like, cultural beliefs, like punishment of infants by beating may cause insecure attachment, and later in life, such narrow-minded cultural beliefs can cause a lower future well-being.
