Mr. Rivero (defendant) and Ms. Rivero (plaintiff) were married and had a child, but got divorced. The Riveros reached a divorce settlement, including a custody agreement under which they agreed to joint physical custody of their child. The agreement stated that Ms. Rivero would have physical custody of the child five days per week and Mr. Rivero would have physical custody two days per week. Less than two months after the district court entered a divorce decree incorporating the agreement, Ms. Rivero filed a petition for primary physical custody. The district court held that the parties had intended with their agreement an even timeshare and that the divorce decree was inconsistent with that intent, because it decreed a five-days-to-two-days split. As a result, the district court modified the divorce decree to a 50/50 timeshare. Ms. Rivero appealed.