How many people do they need to make this happen?
There are 1 or 2 million children in the country...
A little scenario for you to get:
As many civil servants as needed. Good pay. And don't forget that extra bonus if you can detect and classify any of the future's trouble makers, in advance, so Society can make big savings and create a better loving village where everyone will be welcome. Genetic markups will be provided for you to make the right decision... Each Shadow parent will be in charge of 10 children, but based on budget that number may grow to be 100, or more.
Don't forget the bonus, if you can afford the time to do a great job on all 100 cases you will be in charge of, for the next 18 years..."1984" is fiction...
Waste of taxpayers money, the secret service already has all of the data.