With iCloud can family members see what you backed up
With my apple one subscription, I can share iCloud backups with family members. Your not able to see what other family members backed up
Question marked as
For information on sharing an iCloud storage plan and privacy, see the following from: : Share iCloud+ with your family - Apple Support
When you share an iCloud+ subscription, everyone in the family group uses their own account. That way your photos, documents, and other information stay private, even though you're sharing access to the service. You simply share the features and space available in iCloud+ with your family members, so you only have one plan to manage.