don't let your dog eat cat poop.
you will come home from work to find his kennel full of what looks like projectile poop. you will then give him a bath, sterilize everything, take him on a short walk and come home. once you are inside your new house he will then begin to vomit huge amounts of watery cat poop complete with whole, undigested pieces. this will smell worse than anything you've ever smelled and your gag reflex will not be happy. you will start to clean up the first pile while he stands by to vomit six more times. at this point, you'll be aware that what you thought was projectile poop in his kennel was really poop vomit that came out of his mouth, not his butt.
you will call your boyfriend freaking out. he will be on deadline and unable to come home. he will be able to call and get you an appointment at the vet, though.
you'll leave the poop vomit piles in your house on a 90-degree day as you take the dog to the car to drive to the vet. there will be at least one more episode of poop-puke on the way to the car.
once at the vet, the dog will get a thermometer up his butt, a shot to stop the vomiting and some medication for later.
then you'll come home. to a vomit-poop smell that is strong enough to smell from the yard.