Proper syntax for Laravel Eloquent insert/update - laravel

Question

I have seemingly simple problem that I still can't solve after days of browsing around.
Say I have Debitur model.
class Debitur extends Model
{
protected $table = 'debiturs';
protected $fillable = [
'name', 'address',
];
public function debiturWife(){
return $this->hasOne('App\DebiturWife');
}
}
And I have a DebiturWife model.
class DebiturWife extends Model
{
protected $table = 'debitur_wifes';
protected $fillable = [
'nama', 'address', 'photo',
];
public function debitur(){
return $this->belongsTo('App\Debitur');
}
}
I can get Debitur and DebiturWife data in the DebiturController like this:
return Debitur::with('debiturWife')->find($debitur_id);
Now I want to create a new Debitur and DebiturWife, how do I do that?
Something like
$debitur = new Debitur;
$debitur->name = $request->name;
$debitur_wife = new Debitur.DebiturWife; //obviously doesn't work

Answer 1

$debitur = new Debitur;
$debitur->name = $request->name;
$debitur->save();
$debitur_wife = new DebiturWife([
'name' => 'Foo'
]);
$debitur->debiturWife()->save($debitur_wife);
Documentation
What if later I want to update DebiturWife based on Debitur's id?
$debitur = Debitur::with('debiturWife')->find($id);
$debitur->debiturWife->name = 'new name';
$debitur->debiturWife->address = 'new address';
$debitur->save();

Answer 2

You could do this way:
$debitur = new Debitur;
$debitur->name = $request->name;
$debitur->save();
$debitur->debiturWife()->create([
'name' => $request->name,
'address' => $request->address,
'photo' => $request->photo
]);
Another way of doing this would be —
$debiturWife = new DebiturWife();
$debiturWife->name = $request->name;
$debiturWife->address = $request->address;
$debiturWife->photo = $request->photo;
$debitur->debiturWife()->save($debiturWife);
The debitur_id will be automatically set. The only difference between the create & save method is that the create method accepts a plain PHP array whereas the save method accepts an instance of DebitureWife
See the documentation for better understanding.