How many kids are you allowed??- foster/adopt

Our state only allows 5 children in the home at a time unless they get special approal. I too was wondering how I can hear about all these stories of a family adopting 22 children and things like that. I know in most cases those parents accept lots of special needs children and maybe that is why they get the approval because they are in high demand. Or maybe they come from states where there is no limit to the number of kids, I don't know? Maybe you can ask for special permission? I'm sure they would do it if say you are taking a large sibling group since those to are hard to palce and they like to keep them altogether.