Final answer:
In a child with pyloric stenosis, a nurse would expect reports of projectile vomiting, as it is a hallmark symptom of this condition causing the narrowing of the passage from the stomach to the small intestine.
Step-by-step explanation:
The nurse would expect parents to report projectile vomiting in a child with pyloric stenosis. Pyloric stenosis is a condition where the passage from the stomach to the small intestine has become narrowed, leading to forceful vomiting that can shoot out several feet. This condition is typically observed in infants and is not associated with constipation, excessive weight gain, or frequent urination, which can be related to other conditions such as chronic renal disease or gastrointestinal issues during pregnancy.