I have a line where my character is referring to her mother before my character is born. So what does she call her in retrospect? Here is the line. His aging parents—my grandparents—had let the place run down, and after they passed, he returned from Italy with my mother to save it. After four years, I’m still making changes.
I think it's fine as it is. Although she wasn't born yet, she still was her mother, since she have gotten born by her later. At least it doesn't confuse me.
"My soon to be mother"? " My future mother"? Really, your description is fine. The above two are the only possible combos I could think of and I think they're worse than your description.
Yeah, you're totally fine. How do you describe your parents when you reference them in the past? My mother was born in 1949. My father moved to Rhode Island when he was 8. My mom and dad got married in 1972. My parents bought the house I was born in in 1977. My father (according to legend) conceived me in front of the fireplace on Thanksgiving night of the same year, 1977. (I continue to doubt this one. I've seen my dad eat on Thanksgiving. I doubt he was up for the task.) None of those events occurred when they were my "parents." But there is no need to correct for my own conception. My mother was going to be my mother from the moment she was born. At least in this particular continuum.
"My mother" is fine. As a general rule, people don't account for their own non-existence when referring to relative at a time before their own births, because their present is still their default baseline. So, I could be talking about an ancestor of mine who was alive centuries before I was born, but he'd still be "my ancestor" or "my great-great-great-great grandfather", or whatever.
