That would be really hard. I don't have any kids but I pray that if I do they are all Spirit filled Christians living their lives in love. If they were not I would continue to pray for them and still include them in our family Bible studies knowing that one day they will see the Truth. I have a family member or two and some friends that aren't Christian and I pray for them. The Bible says that God is love so if they love I don't fear for their souls, but I do feel that being a Christian is a guarantee into heaven but the Bible also says that if you love God=love and your fellow man then you can also get into heaven. But I know that I want the very best for my children and that is Christianity for me.
Luke 10:25-37 (New Living Translation)
The Most Important Commandment
25 One day an expert in religious law stood up to test Jesus by asking him this question: “Teacher, what should I do to inherit eternal life?”
26 Jesus replied, “What does the law of Moses say? How do you read it?”
27 The man answered, “‘You must love the LORD your God with all your heart, all your soul, all your strength, and all your mind.’ And, ‘Love your neighbor as yourself.’”[a](duet.6:5, lev. 19:18)
28 “Right!” Jesus told him. “Do this and you will live!”
1 John 4
Loving One Another
7 Dear friends, let us continue to love one another, for love comes from God. Anyone who loves is a child of God and knows God. 8 But anyone who does not love does not know God, for God is love.
12 No one has ever seen God. But if we love each other, God lives in us, and his love is brought to full expression in us
16 ... God is love, and all who live in love live in God, and God lives in them.