Should I have the mom alive or dead?

Hello, it's me again. I'm torn on my story.

So my story is that Lee (F 30) goes through her entire life not knowing who her father is and it turns out he's her co-work (M 47). Previously I have her mother (F 46) dead from cancer, effectively ending any confirmation of who her father is.

Now I'm writing flashbacks of the mom and she's just a fun character who's stuck in a really abusive family situation with her own father (M 73) Curtis. Curtis runs a bunch of super churches and because his daughter got pregnant at 16, he kind of just has her constantly under his thumb and working for him.

I'm debating on the mother not being dead. I'm debating when grandpa (M 73) dies she just takes his money and runs with it and is just absent. Lee (F30) just has no clue where her mom is and is happy her mother got away. I'm debating because it would almost certainly be a confrontation between both parents. But imagining her just dropping into her daughter's life and just being an over-grown teenager feels like a fun character to write.

So, keep the Mom dead or alive? If she’s just an over-grown teenager, why would she even drop into her daughter’s life?