navigation properties are not loaded automatically, because they can be expensive. you need to use `.Include(foo => foo.Bars)` to tell EF to retrieve them.

EF tries to be smart and will fix up the property in memory if the referenced entities are returned in separate queries. but if those queries don't return all records in `Foo.Bar`, `Foo.Bar` will only be partially populated.

this can be confusing and is one of the reasons i almost never use navigation properties when working with EF.