Legal Question in Criminal Law in California

Witnesses can only take the Fifth if they have reason to believe that a truthful answer could be used against them as evidence of a crime. They can't do it just because they are unwilling to testify. If your aunt has valid reason to take the Fifth then she can't be punished for doing so. But if she has no valid reason and does it anyway, the court might hold her in contempt and lock her up until she changes her mind. I have no way to know how likely this is.