We are deeply concerned to hear about the challenges you're facing with your identical twin sister. The Bible tells us that "If it is possible, as much as it depends on you, live peaceably with all men" (Romans 12:18, WEB). However, it's important to note that while we should strive for peace, we should also protect ourselves from harm.
Firstly, we want to address the issue of curses and spells. As believers in Jesus Christ, we have authority over such things. Jesus said, "Behold, I have given you authority to tread on serpents and scorpions, and over all the power of the enemy, and nothing will in any way hurt you" (Luke 10:19, WEB). We encourage you to stand firm in this authority and refuse to accept any curses spoken over you or your loved ones.
However, we must also rebuke the practice of curses and spells. These are not from God and are strongly condemned in the Bible. As it is written, "There shall not be found with you anyone who makes his son or his daughter to pass through the fire, one who uses divination, one who practices sorcery, or an enchanter, or a sorcerer, or a charmer, or a person who consults a spirit of the dead, or a wizard, or a necromancer. For whoever does these things is an abomination to Yahweh" (Deuteronomy 18:10-12, WEB).
Let's pray together:
"Father, we come before you in the name of Jesus Christ. We ask that you protect Flewethumn and her family from any harm or evil intended against them. We cancel any curses or spells spoken over them and declare that they are covered by the blood of Jesus. We pray that you will bring peace to their family and soften Flewethumn's sister's heart. Help them to forgive each other and to live in harmony. We also pray that Flewethumn's sister will turn away from the practice of curses and spells and turn to you, Lord. We ask this in Jesus' name. Amen."
Lastly, we encourage you to forgive your sister, as difficult as it may be. Remember, "For if you forgive men their trespasses, your heavenly Father will also forgive you. But if you don’t forgive men their trespasses, neither will your Father forgive your trespasses" (Matthew 6:14-15, WEB). This doesn't mean you should tolerate her harmful behavior, but rather, release any bitterness or resentment towards her.
We also note that your request does not mention the name of Jesus Christ. It is only by His name that we have access to God (John 14:6, WEB). If you have not already, we encourage you to put your trust in Jesus Christ for your salvation.
Articles:
Let's continue to lift up Smilee for complete healing from surgery. "He sent His word and healed them" (Ps. 107:20). Praying for no stiffness, a strengthened and straightened knee, and a perfect walk. Trusting Jesus for a quick return to work. In His name! 
Smilee:
