We understand your concern for your sister Jennifer's salvation and your shared relationship. The Bible says, But as many as received him, to them he gave the right to become God’s children, to those who believe in his name: who were born not of blood, nor of the will of the flesh, nor of the will of man, but of God. The Bible says we have all sinned and fall short of the glory of God. It is only through the conviction of the Holy Spirit that Jennifer will recognize her need for a Savior.
First, let's pray for Jennifer's salvation. Let us pray together: Heavenly Father, we bring Jennifer Mendoza before your throne of Grace. We pray, Father, that you fill her with your mighty presence. We ask for a revelation of your saving power, your purpose, and your presence to be shown to her, Father. We pray that the Holy Spirit will convict her of her sins, of righteousness, and of judgment. As Jennifer is drawn to you, Father, we agree that you will confront her with her sinful lifestyle. Father, your Word says you will bless the work of our hands. We pray for these blessings for her to see the powerful God we serve is you, Father. We thank you that she will confess Jesus Christ as Lord and Savior and walk in the fruit of the Spirit.
Now we need to address your issue with your sister. God's Word reminds us. Let nothing be done through strife or conceit, but in lowliness of mind, each esteem the other better than themselves. Do not just look at your own things, but each of you also at the things of others. Keep this attitude among yourselves, which you had also in Christ Jesus. This attitude is exemplified in the humility and obedience of Christ, who, being in the form of God, did not consider equality with God something to be exploited. But he emptied himself and took on the form of a servant.
In addressing the narcissistic spirit, we must remember that our battle is not against flesh and blood, but against the rulers, against the authorities, against the world's powers of this darkness, and against the spiritual forces of wickedness in the heavenly places. Therefore, put on the whole armor of God, that you may be able to withstand in the evil day, and having done all, to stand. Stand therefore, having the utility belt of truth buckled around your waist, and having put on the breastplate of righteousness, and having fitted your feet with the preparation of the Good News of peace; above all, taking up the shield of faith, with which you will be able to quench all the fiery darts of the evil one. And take the helmet of salvation, and the sword of the Spirit, which is the word of God; praying always with all prayer and supplication in the Spirit, and watching to this end in all perseverance and requests for all the saints.
Heavenly Father, annul the assignment of the narcissistic spirit over the life of Jennifer, and free her from any spirit of arrogance. Let the Spirit of the Lord lift up a standard against these evil spirits. Let every lying spirit in her life be silenced forever. Let the Spirit of humility govern her in all she does and says from now on and remove the veil from her eyes that she might well comprehend the flowing streams of the Lord and humbly serve God and mankind. Let the Spirit of Grace and humility be her portion continually in Jesus' name. We give thanks that the Lord is lifting Jennifer up from the miry clay and placing her feet on the Rock of Jesus Christ. Lord Jesus Christ. we your people praise you for bringing Jennifer to you and placing her feet on the Rock! Roads and corpses shall be in the way. Jennifer is arising and shall come to the knowledge of the LORD our God and the name of Jesus Christ. as the brightness of Your rising. Together with your people Lord, we are confessing to you that you are now lifting Jennifer from the miry clay and setting her feet on the solid rock and place of rest in Jesus Christ. Together we agree that she will always open her mouth to proclaim your righteousness and your praise all the day long. You Lord are bringing Jennifer out of the horrible pit, out of the miry clay, and placing her feet upon the solid rock before you. You are establishing her by bringing Jennifer to be forever to your praise.
Finally, we would caution against a judgmental mindset. Yes, you can be discerning, but that needs to be tempered by love. Make sure you have first addressed your sin. Jesus said, Do not judge, so that you will not be judged. For with whatever judgment you judge, you will be judged; and with whatever measure you measure, it will be measured to you. Why do you see the speck that is in your brother’s eye, but do not consider the beam that is in your own eye? Or how will you tell your brother, 'Let me remove the speck from your eye;' and behold, the beam is in your own eye? You hypocrite! First remove the beam out of your own eye, and then you can see clearly to remove the speck out of your brother’s eye.
Our heartfelt prayer is that God will bring peace and healing to your relationship with Jennifer. Trust in the LORD with all your heart, and do not lean on your own understanding. In all your ways acknowledge him, and he will make straight your paths.
We do not see anywhere in the prayer request that addresses if Lythgyr is a believer. Weapons of our warfare must use the name of Jesus to be successful. There is no other way or motive behind this than the salvation of our immortal souls. We say this because anyone who does not believe in Christ and raise him from the dead is still dead in their sins and will come under the judgment of God and only the name of Jesus can we be saved.