I can’t imagine 4 or anytime before pretty old would I need to tell on myself.
If the desire is so bad, just come out to the world.
If not, you can keep this thing a secret a pretty long time.
The advice about how this can look if the kids talk about daddy’s secret is very good.
I would find a separate place with a lock and a place for all my girlie clothes.
My blue suitcase is mine alone.