Yes, check EVERYwhere!
Even the places where ..."She couldn't *possibly be*!"
THOSE are the places where she probably IS!

On the off chance she DID get out ~
Put a bowl of food out on the porch or steps to draw her close to the house.

But keep looking inside - Boots can *vanish* inside the house, totally ignore frantic pleadings to "Come out, come out, wherever you are!"
...and then saunter into view an hour later with a "Oh, you callin *ME*?" look plastered all over his face!

And he's also spent an entire day locked in the baffroom klozit more than once! SOMEday he'll learn to at least *MeOOOOOw* when he's called!