What can legally be done to get married children with child out of your home. The adults are addicts.

No it is not true, if they do not own the house, you can evict the family. That would have course include their children. Depending on where this is, what type of notice has to be given and if you need specific grounds.

Remember in most areas (in US) if there are drugs in your house and the police raid, the police may even be able to take your home.

Your best bet (there is no good option with addicts) is to privately talk to CPS and arrange to be guardians of the child. You get an eviction order for the parents, and have the police escort them out.

It's going to be awful but it has to be done all in one day, and you need other adults around to protect you after the police leave, because your children will probably try to come back for one reason or another.

You have to legally evict them. However; that is a tough decision as they will take the child. And maybe the child is safer at your home than out on the streets with them.
Might consider looking into a guardianship if you are in position to keep child.
If not, then yes you have to go to court and legally evict them. The court should be able to get them out with 30 days.