Hi, I moved into a 1830's house 3 years ago. The lath and plaster ceiling in the front room in a corner has blown, only occured a year ago. The size of the area is about a meter in area, the corner is at the back of the room. We thought the reason why it cracked was due to the shower directly above, so we have not used it for a year, but it seems to be getting worse can it be repaired?