The Liu family was preparing for a birthday banquet and renovating their courtyard, altering the terrain and drainage during construction. During the rainy season, pooled water flowed backward and affected their neighbor, the Xiao Wang family, resulting in the accidental injury and death of an elderly family member in the Xiao Wang household. Heartbroken, Xiao Wang built his house legally and in compliance with regulations, without any illegal encroachment. Coinciding with a heavy downpour, the Liu family became trapped by accumulated water due to their own terrain issues, and the conflict between both parties was properly resolved.