EF serialize object with nav propertyes - json

Question

I'm creating an API, and I need to send the data model to the client, for easier processing, so I don't need to implement and maintain the json structure on the client side too, just serialize a new empty object, and give it to the client.
But there comes my problem, if the nav property objects are empty, it get
serialized to an empty array
[]
not to the object in the array.
So my question is, can anyone point me to the right direction, to serialize the object with related properties, like how the swagger documentation does it?
Example for base serialization in MVC: http://pastebin.com/ihF2AeKY
Example for serialization by swagger with nav props, and types: http://pastebin.com/SxxztnDa
Now, I can instantiate the nav props, and add it to the object, then serialize it, but that is clumsy, and not following changes in the objects automatically, like the swagger example does.
EDIT:
This would be ideal, since if i change the base object, or prop relations, the model will automatically follow, but since properties are empty in a new object, unless i populate it by hand, the navigational props will be either null, or an empty list like '[]', like shown in the base example, so i won't get the nav props 'scheme', just the base object. Swagger doing some kind of magic here, to build the full tree, shown in the 2nd pastebin.
[Route("getmodel")]
[HttpGet]
public async Task<Company> GetContactCompanyModel(){
var ret = new Company();
return ret;
}
This is kind of working, but clumsy since i need to insert the props with hand, but this will return the correct model, with populated but empty navigational props.
[Route("getmodel")]
[HttpGet]
public async Task<Company> GetContactCompanyModel(){
var ret = new Company();
ret.Peoples.Add(new People { Address = new Address(), PrivateContact = new ContactDetails(), WorkContact = new ContactDetails()});
ret.ServicePlaces.Add(new ServicePlace { ContactDetails = new ContactDetails(), Address = new Address() });
return ret;
}
This is the output of my hand made new() boilerplate :
http://pastebin.com/C4W6Tvsg as you can see, it contains the empty object for the navigational properties, kinda like how EF would return it for me, so i can just send it to the client, and process it with Angular, even if i add new properties, or fields to it.
So in the end, the question is how can i traverse the object graph, and make a schema from it, kinda like if i would eager load it, but with empty objects.
Hope it's a bit clearer like this.