I read https://www.gelderlander.nl/dossier-keldergezin-drenthe/deel-van-de-kinderen-in-boerderij-had-niet-eens-bsn-nummer~a4a43a4c/ https://www.gelderlander.nl/

I read https://www.gelderlander.nl/dossier-keldergezin-drenthe/deel-van-de-kinderen-in-boerderij-had-niet-eens-bsn-nummer~a4a43a4c/ https://www.gelderlander.nl/dossier-keldergezin-drenthe/deel... and it says the some of them did not have a BSN, so were never registered (and the 25 year old said he never went to school in his life).