Imagine six mud-covered, diaperless toddlers and an adult in a white-carpeted room. Serve the kids sugary drinks, peanut-butter-and-Nutella sandwiches, and chocolate ice cream with caramel syrup. For good measure, give the tots some colorful slime to play with, hand the beleaguered parent a bottle of red wine, and then step away for a couple of hours.We simulated this not-inconceivable scenario to test how well carpet cleaners tackle the worst gunk, grime, and goo imaginable. The bad news: We had to throw out the carpet. The good news: Our picks — the Tineco Carpet One Smart Carpet Cleaner and the Bissell ProHeat 2X Revolution Pet Carpet Cleaner — cleaned up most of the stains they were confronted with in our testing.