We are truly saddened to hear about the news of your daughter's baby. In times like these, we must turn to the Lord for comfort and guidance.
We commend you for praying in Jesus' name. The Bible tells us it is only in His name by which we can be saved and be in a relationship with God. Let's remember that. See Acts 4:10-12 WEB
be it known to you all, and to all the people of Israel, that by the name of Jesus Christ of Nazareth, whom you crucified, whom God raised from the dead, by him this man stands here before you whole. This is 'the stone which was regarded as worthless by you, the builders, which has become the head of the corner.' There is salvation in none other, for there is no other name under heaven that is given among men by which we must be saved!.
Regarding your precious grandchild. We as Christians must realize there are several possible outcomes here that could still be faithful and merciful results from God. Please do not presume on God's intent by trying to pray His will or action here. An example would be Mark 13:32 WEB where even Jesus in his ministry on earth does not claim to know God the Father's intent. In short, any outcome should be prayed for as faith that God's plan will be shown in the end. Your daughter's loss could still be considered a merciful blessing if His ultimate goal is considered even if that mercy may not be evident right now. The Psalms of Lament such as Psalm 88 provide such an example. Regardless, only God can know the end results. Yet, as parents God has given us instructions how to pray and act thereby. First Peter 5:7 WEB is pretty clear how to act when dealing with others in suffering. Also see the encouragement of Peter's ultimate goal for us in I Peter 1:3-9.
Another biblical exhortation to remember: Give thanks and rejoice in every occasion including this concerning your granddaughter's fate. Philippians 4:4-8 WEB:
Rejoice in the Lord always! Again I will say, Rejoice! Let your gentleness be known to all men. The Lord is at hand. In nothing be anxious, but in everything, by prayer and petition with thanksgiving, let your requests be made known to God. And the peace of God, which surpasses all understanding, will guard your hearts and your thoughts in Christ Jesus.
Finally, brothers, whatever things are true, whatever things are honorable, whatever things are just, whatever things are pure, whatever things are lovely, whatever things are of good report; if there is any virtue, and if there is any praise, think about these things.
We encourage you to pray for God's will to be done and for your daughter and her husband to trust in the Lord during this difficult time. Pray for their strength and comfort, and that they may lean on the Lord for guidance. A great biblical encouragement to keep in mind when you experience life crashing over us like giant waves causing you to choke out seawater is given by Paul and Peter reminding us that God cares for us exceedingly much by a wonderful illustration with that experience in context. See I Cor 10:13 WEB, I Peter 5:10 WEB, and Isa 41:10.
Let us pray together:
Heavenly Father, we come before You in the name of Jesus, seeking Your will and Your comfort for your daughter and her family. Lord, we ask for Your hand to be upon them, guiding them through this challenging time. We pray for Your will to be done in the life of this precious baby, and for the strength and peace of the parents. Help them to trust in You and to lean on You for guidance. In Jesus' name, we pray. Amen.