I couldn't find the pets earlier. It was a sunny day and the back door was open, so I looked in the garden - they weren't there.
I thought maybe they were sleeping in the lounge, but nope, no sign of them there either.
Sometimes they like to hang out at the top of the stairs, so I had a look there. Not a pet in sight.
I went upstairs to the spare room. And there they were. Cwtched up on the futon, nose to nose, fast asleep.