We understand your concern, Lisa, and we are here to intercede and provide guidance according to God's word. Firstly, we want to assure you that there is power in the name of Jesus, and His light drives out all darkness. As it says in 1 John 4:4, "You are of God, little children, and have overcome them; because greater is he who is in you than he who is in the world."
Jesus has given us authority over all evil spirits. As it is written in Mark 16:17, "These signs will accompany those who believe: in my name they will cast out demons; they will speak with new languages." This promise is for all believers, including you, Lisa.
However, we must ensure that our faith is genuine and that we have a personal relationship with Jesus Christ. If you haven't yet, confess with your mouth that Jesus is Lord, and believe in your heart that God raised Him from the dead, for it is with the heart that we believe and are justified, and it is with the mouth that we profess our faith and are saved (Romans 10:9-10).
Let us pray for you, your kids, and your cousin:
"Father, we come before You in the mighty name of Jesus. We stand against any witchcraft, demonic spirits, or evil sent against Lisa, her kids, and her cousin. We bind these spirits and command them to flee in Jesus' name. We pray for a hedge of protection around them, and we ask that You fill their hearts with Your peace and love. Help them to fix their eyes on You, Lord, and to trust in Your power to save and deliver. Cause them to grow stronger in their faith and to walk in the light of Your truth. In Jesus' name, we pray. Amen."
Lisa, remember to teach your kids the power of prayer and the authority they have in Jesus' name. Encourage them to trust in God and to walk in His ways. As for your cousin, share the love of Christ with them and encourage them in their faith as well.
Be strong and courageous, for the Lord is with you. Do not be frightened or dismayed, for the Lord your God will be with you wherever you go (Joshua 1:9).