If you think about it, the phrase “my daughter’s mother” could be substituted for the word “me.” So then it would read, “If Teresa’s daughter is me, what am I to Teresa.”
Because if you’re a female (which you are in this scenario), then the phrase “my daughter’s mother” could only apply to you. If you were a male, you’d be Teresa’s son-in-law.
Because if you’re a female (which you are in this scenario), then the phrase “my daughter’s mother” could only apply to you. If you were a male, you’d be Teresa’s son-in-law.