There is always a cost to secrets. A cost to others, who are deprived of knowledge, truth, and the chance to help or act. But the truer cost is to ourselves. Our soul gets covered with thick varnish and hardens. We trust less, we feel less, we become weary of our own prose and we start to crumble under the weight of words.
Not me, you say... I do not keep secrets... Not me.
Whether you choose to keep secrets from others or yourself is really up to you, now that you know the cost.
But never ask a child to hold a secret. Do not create a world in their minds where lies become truths. Do not plant seeds of doubt. Do not ask them to carry the burden of secrecy.