It’s a bad desire but it’s an understandable one. I’m so sorry for what you’ve been through anon.
First, understand that the only way he could ever get to Heaven is if he truly has a change of heart and repents for his sins. He would have to change his ways entirely and live to honour God.
It’s not an impossible scenario, and you should pray for him. It’s no doubt terrible and unspeakable what he’s done, but he needs help. When you pray for him, remember that you aren’t doing it just to be nice to him. You’re doing it for God, you’re trying to help one of His lost sheep come back into the fold which He wants.
It’s hard to think about terrible people being in Heaven, or even to think about praying for that to happen. But its’ God’s will not only that we all be saved, but that we all become repentant and actually try to be good people.
There are saints that have done absolutely terrible things. St. Paul for instance, one of the most revered men in all of Christian history, used to pass the time by murdering Christians just because they loved God. And then he realized how terrible those actions were, repented, and became an apostle of Christ Himself.
Nobody is beyond God’s reach.