The ruling on making up the fast of the Day of Ashura if one breaks it

Question:
May Allah bless you. The questioner says that she fasted on the ninth day of the month of Muharram, and just before sunset she experienced a state of nausea, so she broke her fast and also fasted on the tenth day. Does she have to make up this day, or is her fast valid?

Answer:
Her fast is valid. If the vomiting was by her own choice, meaning she caused herself to vomit, then it invalidates her fast. However, if the vomiting overcame her without her choice, then her fast is valid and involuntary vomiting does not affect it. Since she fasted on the tenth day, she has done what is required. If she had missed the tenth day, she would fast the eleventh day along with the tenth, based on the saying of the Prophet (peace and blessings be upon him) . Since the time has passed and she has fasted on the tenth, that is sufficient, and she does not make it up afterwards, as it is a recommended practice whose time has passed.