Praying for the unsaved will accomplish nothing. There's nobody in hell because there wasn't somebody to pray for them. Instead share your faith with them if they're willing to listen. Be a good example for them. But praying that God changes their freewill so they can accept Christ out of their own freewill doesn't make any sense.

If you have an unsaved loved one then God has already put a Christian in their life. We know from scripture that most people will reject Christ.

(Matthew 7:13-14 NIV) "Enter through the narrow gate. For wide is the gate and broad is the road that leads to destruction, and many enter through it. {14} But small is the gate and narrow the road that leads to life, and only a few find it.