Trying to get Medicaid/ FAMIS?

Hello my name is Jason, and I have a question on how to get Medicaid/ FAMIS for my niece, who is 19 years old. My niece, who is 19 years old, is trying to apply for Medicaid, and her mom still has Tricare health Insurance on her, at least it looks like her mom has Tricare Health Insurance on my niece, or her daughter. My nieces mom was in a Prison/ Psychiatric Hospital from April 2008 until April 2011.

When my niece mom got out of Prison/ Psychiatric Hospital, she went and put Tricare health insurance on her daughter(my niece), in April of 2011. My niece mom got a Divorce in June 1997. Her mom was married to a Navy Guy. When they got a Divorce in June 1997 Tricare Health Insurance dropped my niece back in June 1997. But, like I said, when her mom got out of Prison/ Hospital, she went and literally put Tricare Insurance on her daughter (my niece), even though her daughter was dropped by Tricare a longtime ago (June 1997).

So my question is, how does my niece fix this so she can get the Medicaid/ FAMIS that she is really eligible for. Because I don’t think her mom is ever going to change it. Every Health Insurance has a Beginning Date and an End Date. My niece mom did put a Beginning Date on Tricare in April 2011, But her mom never put an End Date, or the Date Tricare suppose to had Ended. Even though Tricare Ended in June 1997, But because my niece mom will not put an End Date, my niece cannot get the Medicaid/ FAMIS.

I even ask her mom can she put an End Date, and her mom literally will not do it. I know and I agree that that is a terrible thing for her mom to do. So what should my niece do? My niece mom has a Mental Illness, and was on Medication on April 2011. But, what can my niece do, because she needs Medicaid/ FAMIS, and is eligible for it.