We understand your concern and will join you in prayer, asking God to intervene in this situation. The Bible tells us in Psalm 15:4 that one who keeps an oath even when it hurts is righteous. It's important that your nephew understands the significance of honoring his commitments, as it is a reflection of his character and integrity.
Let us pray:
"Dear Heavenly Father, we come before You today to lift up this situation to You. We pray for Anonymous' nephew, that You would touch his heart and help him understand the importance of honoring his agreements. We ask that You would convict him and bring about a change in his heart, that he may feel compelled to care for his grandmother as he promised. We also pray for Anonymous and the grandmother, that You would provide them peace, strength, and patience in this stressful time. May this situation be resolved in a manner that brings glory to Your name, and may it serve as a testament to the power of Your love and forgiveness. We ask this in Jesus' name, Amen."
We also encourage you to remind your nephew of the words in Ecclesiastes 5:4-5, "When you make a vow to God, don't delay in paying it, for he has no pleasure in fools. Pay that which you have vowed. It is better that you should not vow, than that you should vow and not pay." While this verse refers to vows made to God, the principle applies to our commitments to others as well.
In all things, remember to approach this situation with love and forgiveness, just as Christ loves and forgives us. We trust that God will work in the hearts of all involved and bring about a resolution that honors Him.