Must the father make up for the day he broke his fast only after he swore in anger, "By Allah, I will not fast the remaining days of Ramadan," and then he returned to fasting?

It is not permissible for a Muslim to swear an oath to abandon what Allah has made obligatory upon him. If he does so, he has sinned and repentance becomes incumbent upon him. He must then break his oath by fasting the remainder of Ramadan. He is also liable for an expiation for breaking an oath and must make up for the day he broke his fast. Furthermore, he must repent for breaking his fast. The jurists have explicitly stated that it is obligatory to break an oath made upon a sin. Similarly, it is not permissible to express discontent with the decrees of Allah Almighty.