Hi had bathroom refurbished 4/5 years ago. A few years ago I noticed a vertical crack on tiles from ceiling down through 2.5 tiles. Looking today it’s actually through the rest of the third tile and there is a crack going off at an angle from original crack on top tile. Also on the top tile it’s as if one side of the crack sits slightly higher than the other side. I actually cut my finger whilst having a look at it. The area in question was not tiled originally and there were no visible cracks on wall prior to work being carried out. The tiles were laid on plywood. My son can spend hours in shower and we have lots of condensation. Could it be this or perhaps truss uplift? Thanks for your help. iCloud - https://share.icloud.com/photos/0pqAQGVZHWtgADVwjGoFfWfkw