I have tried multiple things that don't work for some reason. I have loaded up a save before I bought the house, I have deleted and re-downloaded the Hearthfire DLC, but I still can't move my family, so nothing works! I think it's because I don't own the house. Will someone please help fix this problem?
As you said in your comments, you can't move your family. First, if you're having children, make beds and a container either on the upstairs floor on the left or in the bedroom wing. Make sure you also created a container for them to store too! Second, make sure you furnished your house. it doesn't need to completely be furnished, but it must not be a bit empty.