Khaoz894
When Palpatine commits a mistake and has a child, he hides him from his master, however, it doesn't come from a place of affection, for Palpatine sees potential in y/n, and he desires to use him to carry out his plan of conquering the Galaxy alongside Maul.
When that doesn't work, Palpatine must rely on y/n to do most of the groundwork, and y/n obeys. Because there is no more loyal and blind apprentice that the one who is your blood.
But unfortunately, all Sith have a weak point. And not even the most blind one is capable of getting rid of such a weakness.