what will cause family services to step in and take children out of a home?

[Angel Rose]

I had asked a previous question before about this family but after talking with a good friend of mine, there are some drawbacks....I was told that a family doesn't have to have a clean house, that social services aren't picky about this, and there has to be marks of abuse on the child. This family in question lives in a filthy house but there are no signs of abuse to the child. I was also told that if social services comes in and doesn't find the house is dirty enough to remove the children the downside is this family will think there is nothing wrong with their filth and it will only get worse? Is this true? What are some of the factors of filth that they look for?

See previous question for more details.