...Such intolerable confusion about a child’s family background [e.g. secret] can be the cause of learning problems in school (because knowledge is forbidden and thus is threatening and dangerous).
This rings a bell! What was forbidden and thus is theratening and dangerous? In my case it was not knowledge (not family background), it was – what? What was forbidden? To feel, to be authentic. But there was more. Something was forbidden. Maybe there was some secret, maybe it was forbidden to tell the truth? To be truthfull to oneself? I know for sure my mother felt she was denied happiness. I wish I could knew about that in more detail. Maybe happiness itself was forbidden and thus remained threatening and dangerous.
That is how i feel often, in those moments when i want to pursue some happy activity (usually sports). I instantly loose all interest, and I say to myself- do I really want that activity? And something feels wrong and I conclude, no, I don’t really want it. But later I realise it was not the case.