a resonable ... reason?

A couple of days ago, somehow the water in the sink was turned on - and stayed on for at least an hour. All the hot water gone.
I didn't do it. Shahhe didn't do it. Hubby says he didn't do it. AND he wanted me to appologise for doing it.
He wanted me to appologise for something I didn't do.
Now, beyond the fact he wanted me to appologise for something I didn't do, the glaring question in MY mind is...

How did the water turn on?