Most schools look favorably on an upward trend but I wouldn’t say they ignore Fresh/Soph years. And Ivies don’t really have to ignore anything since since they have so may high stats applicants. You should be sure you have some other safeties lined up. What’s your SAT/ACT? Do you have AP or SAT Subject Test scores that reinforce your Junior/Senior grades?
I have also seen comments on here indicating that schools might start shying away from students with mental health issues b/c colleges are becoming overrun with that and don’t have the capacity to provide support. Not sure if its true but you might want to focus your explanation on the family issues and school transfer and not mental health.