If I were you
cmacleod42 I'd consider removing the Mom/Gabby as a dead end. The Mom is part of an incest fetish which is rampant across adult games so will be a "high value target" so to speak. Having her be one of the very few targets who can be locked off permanently doesn't really help replayability, it just means people come on here or the other place to ask you how to get them and which variables to change to reset the story.
If you are married to the idea, then perhaps in the Cheat menu a "reset Mom and Gabby" button could be setup. Judging by this thread it would save a good 30% of support requests.