I’m sure it has happened that an adult is arrested with children in their car or house. What do the police do with the children? I could see this being a problem if the adult is intoxicated, injured, or otherwise unable/unwilling to provide information about a family member who can care for the child. What if there is no family member? Is there a “holding cell” for the foster care system?
Various social services agencies usually have emergency foster care placement that can be done in a few hours. I guess for those few hours the kids just hang out with the social worker to whom the police handed them off.
Our first choice is to get the arrested person to identify who they want to take the child. If they can’t or won’t name someone, then we turn the child over to Child Protective Services.
This is in Washington state, but I’m sure the procedure is pretty much the same everywhere.