The same thing happens to puppies, of course - but it's a rare occasion that sees a puppy dog's owner in possession of a video camera to record their sleepiness.
Here, a really rather adorable pooch gets so pooped he starts napping standing up, and then gets so sleepy he collapses into a bundle of cute and wakes himself up in the process. In a word: "Naw..."
For more "Naw...", check out this video gallery we've got for you below of cats and dogs getting on like a house on fire - often napping together, in fact.
Taking care of each other.
And an ear cleaning.
They're ok hanging out with each other while the other cats play.
Spots, no spots. It's cool.
GIMME A HUG!
I think you've got something in your ear.
There's plenty of room in that bed.
Let me just get those knots in your shoulders out.
Exhausted after a day of hanging out.
That puppy's fur does look pretty warm.
A playful cuddle.
Shhhh. She's sleeping.