Entity Framework will only set related entity property to “null” if I first get the property

Question

Edit This seems to occur for any Entity property that references another entity in one direction. In other words, for the below example, the fact

Answer 1

You are right - this happens beacause you used lazy loading in EF (virtual property). You may remove virtual (but this may be impossible for you). Other way you described in your question - call property, and set this to null.

Also you could read another topic about this problem on SO.