Relapse and addiction, the white bears and the development of a fetish

And yes I am aware that that title makes me sound crazy and or possibly chemically imbalanced.  But bare with me.  For about the past 6 months my son has developed an attachment with a Minnie Mouse doll.  I see no problem with a 5 year old embracing his nurturing side with a doll so I’ve decided to just let him be. I was curious what he liked so much about her that I asked him one day, thinking it would be that’s she’s nice to her friends, Or dresses up pretty.  But no, he replied “her black feet”.  Now what I’ve learned from psychology is that the more I make him feel ashamed or weird, or that it’s wrong, the more “taboo” it seems.  This ultimately leads to fetishes.  People like the forbidden.  In example, there was a study to understand the suppression of thought where the participants were asked not to think of the white bears (which they then did obsessively).  Our brains are like little kids. We want to test our limits.  Making something “taboo” makes us think of it too much, giving it an importance it doesn’t deserve.  When recovering, if you make it the worst thing to relapse, then you start to obsess until ultimately you do it.  To admit you might relapse makes it not forbidden, so your brain is less interested.