Let's address your request directly for a heartfelt assessment.
Firstly, it's important to acknowledge that God is indeed merciful and forgiving.
In Psalm 103:8-12 (WEB)
The Lord is merciful and gracious, slow to anger, and abundant in loving kindness. He will not always accuse; neither will he stay angry forever. He has not dealt with us according to our sins, nor repaid us for our iniquities. For as the heavens are high above the earth, so great is his loving kindness toward those who fear him. As far as the east is from the west, so far has he removed our transgressions from us.
However, we must also address that forgiveness does not mean that there are no consequences for our actions. The father of your children committed a serious crime, and while God can forgive him, he must still face the earthly consequences of his actions.
In Galatians 6:7 (WEB)
Don't be deceived. God is not mocked, for whatever a man sows, that he will also reap.
While you pray for mercy, remember that true mercy also involves helping him take responsibility for his actions and encouraging him to repent sincerely. True repentance can even be a testimony to others in prison. His relationship with God affected by Jesus Christ and proper confession and restitution are paramount.
In 1 John 1:9 (WEB)
If we confess our sins, he is faithful and righteous to forgive us the sins, and to cleanse us from all unrighteousness.
For you personally, it's wonderful to hear you're aligning with God's will and working on forgiveness.
In Ephesians 4:31-32 (WEB)
Let all bitterness, wrath, anger, outcry, and slander, be put away from you, with all malice. And be kind to one another, tenderhearted, forgiving each other, just as God also in Christ forgave you. As children of disobedience.
You are right to approach God in the name of Jesus and a good outcome on the testimony of Jesus.
In John 14:13-14 (WEB)
Whatever you will ask in my name, that will I do, that the Father may be glorified in the Son. If you will ask anything in my name, I will do it.
Continue lifting him up in prayer, that he should find a godly sorrow that leads to repentance and developing a new relationship with Jesus.
Let us pray together.
Father, we come before you in the name of Jesus, lifting up the father of Hisscelot's children. We know that no sin is too great for your forgiveness, and we pray that he would truly repent and turn to you, being encouraged by the presence of Jesus. We pray for mercy and wisdom for the authorities involved, and for healing and provision for Hisscelot and her children. Help her to forgive completely and to trust in you for all things. May anyone looking recall these things and believe in Jesus for their own salvation according to Your will. We ask this in the name of Jesus, Amen.