We understand that you're going through a challenging situation, and we're here to pray with you and offer biblical guidance. Firstly, we're glad that you mentioned Jesus' name, as it is only by His name that we have access to God. Remember His name is the only name by which we can be saved.
Let's address the issues you've raised. Firstly, it's important to remember that God wants us to be content and joyful in all circumstances, as it says in Philippians 4:11-13 WEB: "Not that I speak because of lack, for I have learned in whatever state I am, to be content in it. I know how to be humbled, and I know also how to abound. In everything and in all things I have learned the secret both to be filled and to be hungry, both to abound and to be in need. I can do all things through Christ who strengthens me."
Regarding your grown children in their late 20s, it's important to remember that God calls us to be responsible and to work diligently. As it says in 2 Thessalonians 3:10-12 WEB: "For even when we were with you, we commanded you this: 'If anyone is not willing to work, neither let him eat.' For we hear of some who walk among you disorderly, who don’t work at all, but are busybodies. Now those who are that way, we command and exhort in the Lord Jesus Christ, that with quietness they work and eat their own bread."
It's also important to remember that God calls us to be wise with our finances and not to enable irresponsible behavior. As it says in Proverbs 22:7 WEB: "The rich rule over the poor, and the borrower is servant to the lender."
Regarding the individual who is trying to manipulate you financially, remember that God calls us to be wise and to set boundaries. As it says in Proverbs 22:3 WEB: "The prudent see danger and take refuge; but the simple pass on, and suffer for it."
Let's pray together:
"Father God, we come before You in Jesus' name, lifting up our brother/sister in faith. We thank You for the work they have completed, and we pray that You would bring joy and contentment into their life, regardless of the circumstances. We pray for their grown children, that they would take responsibility for their own lives and learn to work diligently. We pray that You would give our brother/sister wisdom in setting boundaries and being a good steward of their finances. We pray that You would soften the heart of the individual who is trying to manipulate them, and bring conviction and repentance. We pray that our brother/sister would remain strong in their faith, and that they would continue to trust in You, no matter what. In Jesus' name, we pray. Amen."
Remember, God is faithful and He cares for you. Trust in Him, and He will see you through this challenging time. Keep your eyes fixed on Jesus, and He will direct your paths.
Prayer Focus: God, Thank You. Thank You for loving me. God, I ask You in Jesus’ name bless me with everything that I stand in need of and everything You want me to have. Bless me to know You in truth, fall in love with You with all my heart, mind, soul, body, and strength and never fall out of love with You. Bless me to have an ever growing closer stronger, more intimate relationship with You. Bless me with the love, desire, strength, and the spirit of obedience to always delight myself in You, seek first Your kingdom, and Your righteousness. Help and strengthen me God to always respect and obey You. Bless me to trust You with all my heart, acknowledge You in all my ways, and lean not to my own understanding. 
