Soft delete account and hide all its child entities from Siebel UI

Hello - We've a requirement where in some scenarios business wants us to soft delete account record (NO hard delete) and hide it from Siebel UI  (In My, My Team, All and All across Org view). Also once account is soft deleted business wants to hide its child entities in Siebel UI as well(e.g. contact, activities, Service request, Quotes, Orders etc.)

How could this be done without hard delete?

Thanks