Stinky Sheets

That's weird b/c I always thought they didn't actually poop while they were sleeping. Before he falls asleep maybe? After my son went to bed, I always checked him before I went to bed and if there was a smell.....I really mastered the art of changing him without waking him up! I just couldn't stand the thought of him sleeping in a poopie diaper, I guess. I'll bet you could try that. Good luck. Otherwise, I'd just change his sheets very frequently.

my suggestion was just to put a bathtowel down on top of the sheets and either air or wash them after each sleep

What about spritzing the sheets each morning with Febreeze (as long as he doesn't have sensitive skin)? By the time he lays down again for nap the sheets should be dry and smelling fresh. Or if you want something more natural what about buying lavender oil and putting a few drops in with water in a spray bottle, then spritzing the sheet with that?
Hope this helps.

They make pads you can put in the crib/toddler bed
That keep the sheets clean just in case of a leak or
Or something, then all you have to do is remove the pad
And clean that instead of stripping the sheets every day.
They are similar to pads they use in hospitals on top
Of the sheets, except these come in colors and can
Tie onto the side of the crib to secure them in place.
When my 2 boys were little they were a God send otherwise
I would have changed the sheets much more often. I believe
I bought them at Babies R Us. Good Luck!

I would try using vinegar when you wash the sheets (at least a cup or more- I just dump it in). It seems to help remove odors.