Blackbird, bye bye.

I came downstairs this morning to discover a blackbird in the lounge.
It was a very lucky bird not to have fallen into the clutches of two cats who seemed as surprised as I was.
I opened doors and windows and it managed to get out, but I spent all day wondering how it had got in.
Had one of the cats brought it in?
Had it hopped in through an open window?

It was only when I got home this evening I saw exactly how it had made its entrance!!