Help! My cats keep weeing on my sofa

[mychildrenaredrivingmemad]

A couple of weeks ago I discovered the cat had done a wee on the sofa whilst we were out and the babysitter was here. I cleaned scrubbed, used stain remover, steam cleaned it and used fabreeze, Thought I had sorted it, but a couple of days later (whilst we were away and a neighbour was feeding them) they did it again. Same rigmarole again. I wondered if it was an anxiety thing, but then I woke this morning (we were here yesterday) to find they had done it again. Sorted it out again, went out this evening and came back to more wee on the sofa and in our children’s room.

I know it is fireworks tonight and that might be an issue, and I have recently changed the litter to the wooden sort. Could it be either or these things causing this? And does anyone have any ideas as to how your stop them doing it? My husband is really not impressed (we talked him into getting these cats) and I am getting the brunt of his frustration