Is expiation required for someone who swore not to go to his father, then forgot his oath and went to fulfill his father's request without reaching him?

The oath that flows unintentionally from the tongue, such as saying "No, by God" and "Yes, by God," is considered a vain oath (laghw al-yameen), and there is no expiation for it, as Allah Almighty says: "Allah will not impose blame upon you for what is unintentional in your oaths, but He will impose blame upon you for what your hearts have earned."