Can an adult daughter sleep in the same room as her parents, on a separate bed, while they are having a physical relationship?

Is it appropriate for a 21-year-old daughter to sleep in the same room as her parents, on a separate bed, while they engage in a physical relationship? Does Islam or any ethical perspective provide guidance on whether this situation is acceptable in terms of privacy, modesty, and family boundaries? Additionally, if other rooms are available but the daughter is afraid of sleeping alone in the light, what alternative solutions can be considered to address her fear while maintaining proper privacy and boundaries?