We are truly sorry to hear about the struggles your daughter is facing, and we are here to intercede and offer guidance in the name of Jesus Christ. Firstly, we commend you for your love and concern for your daughter. Although this situation is challenging, God promises He will never leave nor forsake us, as stated in Hebrews 13:5 (Please note all scripture is quoted from the World English Bible:
For he has said, "I will never leave you, nor forsake you.")
Let us pray together:
Dear Heavenly Father,
We come before You in the name of Jesus Christ, lifting up our sister who is battling severe migraines, depression, and anxiety. We pray for Your healing touch upon her body and mind. Comfort her and give her the strength and courage to face each day.
Lord, we ask that You provide her with a suitable place to live, where she can find peace and stability. We know that You are a loving and providing Father, and we trust in Your provision for her.
Father, we also pray for her son. We ask that You watch over him, protect him, and provide for his needs. We pray for a godly reuniting of mother and son, in Your timing and according to Your will.
Lord, we pray for her work situation. We ask that You grant her favor with her employers and that You provide for her financially. Guide her steps and open the right doors for her.
Father, we also lift up her mother. We pray for Your intervention in her mental health struggles. We ask that You provide wisdom and guidance for the family as they navigate this difficult situation.
Lord, we pray for a restoration of relationships within this family. We ask that You heal any brokenness and bring them closer to You and to each other.
In the name and by the blood of Jesus Christ, we pray. Amen.
Additionally, we encourage your daughter to cast all her anxieties on Him, because He cares for her, as per 1 Peter 5:7. "Casting all your worries on him, because he cares for you."
Although the situation is tough, the apostle Paul reminds us in Romans 8:28, "We know that all things work together for good for those who love God, to those who are called according to his purpose." Trust that God is working even in this difficult situation and will bring a hope and a future for your daughter and her son.
Finally, it is important to remember that it is only by the name of Jesus Christ that we have access to the Father. As per John 14:6 (WEB),
Jesus said to him, "I am the way, the truth, and the life. No one comes to the Father except through me." This truth is vital for every Believer as well as every prayer request.
Please continue to trust in the Lord and stand firm in your faith. Keep praying and interceding for your daughter, and we will join you in this as well. The Word commands us to pray without ceasing as per 1 Thessalonians 5:17. So we pray with you.
Prayer Focus: God, Thank You for loving me. God, I ask You in Jesus’ name please bless me with everything that I stand in need of and everything You want me to have. 
