My dd is the same!! she is 2.5
She has to either wear a wooly hat or an alice band FAME style around her head!! no matter what the weather. And noone absolutely noone can help her put them on, touch them when they are on or do anything with them! The amount of busy bodies i see smirking or giving me odd looks like "why are you dressing your dd in a woolen hat when is is so hot?"
I like to think i'm allowing her her individual style .
She also has to tell us the same story every night before bed (and we must not interupt otherwise she has to start all over again!)
Virtually everything she decides to do must not be interrupted otherwise we have to go back to beginning. TO the point of going back to front door if i've tried to help her towards the car!!
I havn't been overly concerned about this, me and dp do sometimes roll our eyes and mouth OCD at each other in a jokey way. (i am not knocking the seriousness of OCD btw).
I recently did some work with a counsellor who specialises in OCD and so i mentioned dd to her. And she basically said OCD is present in everyone and it is only a problem when it begins to affect daily life/when the loses control of their behaviour over OCD.
These things are far more apparent in young children as the stage of development means they are learning about control and to some extent this is healthy and does not mean they will suffer as they get older.
I know some people reading this will think dd sounds spoilt. But its not that, it is genuine obsessions and i am taking a very careful approach with them to ensure they don't become a problem. I try to reassure her that if she does forget her hat one day it doesn't matter and we talk about the fact that we need hats in winter when its cold, but its ok in the summer becuase its hotter etc...