Stains on the Ceiling

[Sloughman]

Please help. I have a problem with a roof that has been installed in 2006. I had condensation (mold) in ceiling of all three rooms for 12 years then Installed roof vents. The mold disappeared from all the rooms and sometime 6 years ago this started but it was small at the beginning. However it is getting bigger every year. The confusing thing is that the wall does not become wet when it rains. Also on the other side in the neighbouring house exactly the same place as my house, they don’t this problem. So is this rain water leaking in from the roof or a condensation?

[Someone-Else]