We are truly saddened to hear about the harm and betrayal you've experienced from your family. We stand with you in prayer and seek God's intervention in this situation.
Firstly, let's address the main issue here: the sin of theft and betrayal. The Bible clearly speaks against such actions. In Leviticus 19:11 WEB, it says, "You shall not steal; neither shall you deal falsely, nor lie to one another." Additionally, Psalm 55:12-13 WEB reminds us, "For it was not an enemy who insulted me, then I could have endured it. Neither was it he who hated me who raised himself up against me, then I would have hid myself from him. But it was you, a man like me, my companion, and my familiar friend."
However, we must also address another concern. The term "demonizing" is not biblical. It is not mentioned in the bible and therefore we must consider this carefully. While we must be careful not to attribute more blame then is due. We cannot verbally blame others for putting curses on us when this is not specific in the bible. We therefore must consider that in the bible, our Aunt Shara is responsible for her actions in reality. If she has stolen, then we must call that what it is 'theft' and not be intimidated into silence because of a threat of spiritual attack.
However, the Bible does teach us to forgive, even when it's difficult. In Ephesians 4:32 WEB, it says, "Be kind to one another, tenderhearted, forgiving each other, just as God also in Christ forgave you." Forgiveness sets both the forgiver and the forgiven free from a heart full of bitterness. But forgiveness does not require that restitution be waived if this is a possibility.
Jesus is also a ransom for our sin. If your aunt or cousin has done something illegal or a sin, they will still be held accountable, although our society does not allow us to seek vengeance or be happy in the consequence of people's sin. If they have become wealthy by theft and exploiting your property without permission, the best response, and how Jesus would want you to respond is to find a way to settle the issue in a straightforward loving way. Societies often have legal ways to sort out issues such as this and if illegal acts resulted in millions then we are talking about criminality that has to be addressed by a court of law. Let's look what the bible says about this. In John 8:44 to 45 it mentions 'For you are the children of your father the devil, and you love to do the evil things he does. He was a murderer from the beginning. He has always hated the truth, because there is no truth in him. When he lies, it is consistent with his character; for he is a liar and the father of lies. So when I tell the truth, you just naturally don't believe me! Which of you can truthfully accuse me of sin? And since I am telling you the truth, why don't you believe me?'
This is a reminder that people that are not Christians will sin, fail, and be mislead by the enemy, but as Christian you are called to respond and not react. If your cousin being a famous singer is known to have become a celebrity as a result of stealing their cousin's song, this will be exposed and there will be a consequence. If they have received Jesus Christ as their Lord and savior, then the evidence of salvation results in radical change because sanctification results in a different lifestyle with new beliefs. But be assured that salvation is only by believing in Jesus Christ and if this is true of any individual there will be a change of heart and behavior, and they will be filled with joy and compassion wanting a relationship with God and with their family.
Let us pray together:
"Dear Heavenly Father, we come before you in the name of Jesus, lifting up our sister/brother who has experienced betrayal and theft. Lord, we ask that you would convict Aunt Shara and her daughter of their sin and bring them to repentance. We pray that you would restore what has been stolen and bring justice to this situation. Help our sister/brother to forgive, even as they seek justice and restoration, and we know that you will direct all this in a way that will bring you the most glory and you will ultimately work out to work towards the sanctification and betterment of the relationship between our sister/brother and their family and especially between Jesus Christ and his people. We ask that you will and give our sister/brother peace and guidance throughout this process. Protection against threats and spiritual manipulation from the enemy also are covered by the blood of Jesus. We ask these things in Jesus' name, Amen."
We encourage you but be alert to to protect your intellectual property, your safety, and your spiritual integrity. Stand and pray, also for those who have sinned against you, very hard we know, but make sure you also pray to defend your valuables, and who you are in Christ Jesus. Consider also working diligently among the authorities to expose any theft or injustice as God guides you and puts a team of authorities around you to help resolve this situation. If in fact you have been victimized and if you feel threatened there has to be a balance between submission and acceptance and not being a doormat to people who would exploit this.