If a wife who is observing a supererogatory fast fondles her husband who is not fasting, and he ejaculates, does her fast become invalid?

A woman's fasting is not related to her husband's ejaculation; rather, her fast is valid as long as nothing invalidating it comes out of her. If semen is discharged from her due to foreplay, her fast is invalidated by scholarly consensus. However, if pre-seminal fluid (madhiy) is discharged, her fast remains valid according to the most preponderant opinion.