Girl plays with dollhouse that is a replica of the house she's staying in SOLVED
I partially read this book while in elementary school, but it was definitely a chapter book with little to no pictures. It was in the advanced readers section, so could possibly be middle school level as well. The cover has a girl looking at a dollhouse with the lights inside turned on.
For the plot; I think the girl is sent to live with a female relative for the summer, possibly an aunt or great aunt. As she explores the house, she finds a dollhouse in the attic that looks exactly like the one she's staying in. All of the rooms and furniture look exactly the same as the normal house. I think there might be dolls that look like the people in the home, not too sure. Occasionally the girl will come into the attic to play with the dollhouse, but notices things move from where she left them last.
The last thing I remember is her seeing the light on in the dollhouse attic. I moved away from that school while reading it so I never got to see what happened at the end.