I think someone is coming into our back garden. Today and Sunday morning , the garden tap has been turned on and the hose adaptor pulled off so it is spraying on the floor until we notice.
On Sunday I thought that we had left it turned on (with the hose attached we wouldn't know ) as the hose and adaptor were on the floor nearby and maybe the pressure made it come off. But its happened again and I know for sure we have not turned the tap on, and the adaptor seems to be missing.
What's going on?! We have had a new fence and gate recently so it is high and sturdy. The only other way someone could get in is via next doors garden, then climbing on things to get over that lower fence 
We have known of 2 occasions in the past (we have lived here a year) where someone has 100% been in the garden because the plastic shed lid was left up. But we had our old rickety fence and broken gate back then. Someone kicked it in we think as it was hanging off anyway so we had no gate for a couple of weeks. We haven't had that problem since getting the new fence up as they wouldn't be able to get in now. (There was a footprint on the gate when we first had it put up, so some one tried to kick it down, but had nothing of the sort for a few months.
We also put up security lights In that area.
Next step, we will get a camera! Why would someone do this?