Does striking or disinheriting the children of a deceased brother, with whom you live and who regard you as their father, fall under the forbidden oppression of orphans mentioned in the noble verse: "So as for the orphan, do not oppress [him]"?

It is permissible to interact with orphans with the intention of improving their affairs, just as one would interact with one's own children. The guardian must teach the orphan matters of this world and the hereafter and discipline him as he would discipline his own child, even if it leads to striking, as long as it is for correction and not for revenge. One must be careful about letting children watch television due to the religious prohibitions it contains.