follow up with social services child abuse?

Hi
I made the child abuse report and the case worker called me but how do I know if they went out to the house.
If you read my post last week, I had made a report because my great nephew is being abused by his parents (my neice and the boys father are doing meth and physically abusing one another in front of the liittle boy)

Here’s the thing, my niece hasn’t said anything about it to me or her mother ( my sister)
My sister and I both agree that if the caseworker came out then the she would have said something to her mother but nothing has been said.

How do I know they even investigated the report, do I call back?
I seen my niece last week after the call and she had a black eye, now I know this is going on still.

What do I do.

Thanks