Many comments in Argentine news sites also brought up the fact that the poorer kid seems to be cribbing noted from the other one - by which Clarín no doubt meant to reinforce the notion that "the poor are always trying to steal from the well-off" (and perhaps some do - but as Trump and the Macri know so well, so do the very wealthy).
The fact is that besides the racist innuendo, the Clarín piece deliberately left out the fact that private schools in Argentina receive over $1 billion in state subsidies annually - and that's just at the k-through-12 level. The City of Buenos Aires alone doted over $350 million of this total.
This is on top of the fact that nearly all these schools function as non-profits and are even exempt from payroll taxes.
I think it's safe to say that their performance - which is already no better than public schools once the social status of the children therein is taken into account - would be a good bit worse were it not for these subsidies.
As for the Bullriches: yes, they are indeed related. They are third cousins, descended from a German immigrant named August Bullrich (their great-great-grandfather). Born in Berlin, he arrived in Buenos Aires in the very early days of Argentina, around 1830, and by the time he died in 1882 owned the largest cattle auction house in the country at a time when cattle ranching was king in Argentina (it's only 2% of the economy now).
I don't subscribe to the belief that all people born into privilege have an outsized sense of entitlement - but these two definitely do. They dishonor their very good fortune, really.