What is this fascination?

What is this look of intently watching something?

(And no, it's not the giraffe, that his finger is resting on.)

What is so interesting, that Ethan has to peer down the hall to see it?
What is behind these closed doors, that he wants so badly to come out?
It's nothing more than our vacuum cleaner!
Phew! Now I can see it in action. That's my boy! Someday he's going to be a big helper around the house, just like his daddy.