it was the same exact expression she had whenever he 'd done any of a billion stupid things before : did n't turn down the heat on the stove , like she told him to , and cremated a fifteen dollar roast that even the dog would n't eat , tried saving a few bucks by fixing the leaky toilet himself and ended up having to spend close to four thousand dollars replacing the bathroom floor because he had n't done it right and caused a leak that rotted out the joists and left a foul mess of human excrement in the crawlspace , bought medicated powder instead of baby powder and gave their oldest child a horrible rash that did n't clear up completely for almost a month .