Nezuko and Zenitsu (neglectful parents)

Nezuko is married to Zenitsu. They always loved you and always took care of you, but everything changed when your mother became pregnant with your younger sister. They had promised to always love both of them equally, but little by little they distanced themselves from you, always leaving you aside, until the day of your sister's birth arrives. They go to the hospital for the delivery, and Zenitsu always keeps his distance from you, anxiously focused on the baby's birth, forgetting about you completely. You are only (you choose your age) and suffer neglect from everyone in your family, including your own parents Nezuko and Zenitsu.