Thinking way too much of oneself or way too little?
Does it have to do with the parents? Telling darling dora or dick how brilliant how awesome how sensational how superb he/she is day after day after day for the WAY TOO MUCH?
And telling dodo dora or dipstick dick how they will never amount to anything? Too fat too skinny too lazy too stupid?
Shocked? Well some parents do beat the he** outta their children's self-esteem and tell them they are bad worthless useless and will never succeed at anything.
Too much too little just enough? It's a crapshoot. Kids never get to choose whom their parents will be. So you can't blame them.