I heard it had something to do with them watching their mom clean up...so they clean up... and then i think maybe it's to do with being scolded and they think well if i clean it up mommy/daddy never knew it was there...
and then their missing something or it's not entirely digested so they figure hey why not re-eat what i... (you know the rest!).
My moms Boston puppy did that and we read up on the net that to give them plain yogurt and it worked for her!
Good Luck!
