How do I retrieve the related models of related models of a model?

Have you established Eloquent reationships or you need help with both query and relationships?

Actually, I don't know how to make this into a relationship. I already have the query, I just need to know how to use it in the model.

In Location:

public function crimes()
{
    return $this->hasMany('App\Crime');
}

public function suspects()
{
    return $this->crimes->flatMap(function ($crime) {
        return $crime->suspects;
    });
}

In Crime:

public function location()
{
    return $this->belongsTo('App\Location');
}

public function suspects()
{
    return $this->belongsToMany('App\Suspect');
}

In Suspect:

public function crimes()
{
    return $this->belongsToMany('App\Crimes');
}

Query (Simple Enough if I got you right):

$crimes_in_that_location = $location->suspects();

Should do the job. ;)

please do use proper code blocks when posting codes.

Call to undefined relationship [suspects] on model [App\Location].

If that was as easy as this, I wouldn't have posted a lot of questions in the internet.

I mean, I need to retrieve the suspects directly as a colleciton of model for Location. Not the Crimes in that location, but the Suspects in that location.

In the location model:

protected $appends = ['suspects'];

public function allSuspects(){
    return DB::table('crime_suspect')
                ->leftJoin('crime', 'crime_suspect.crime_id', '=', 'crime.id')
                ->rightJoin('suspects', 'crime_suspect.suspect_id', '=', 'suspects.id')
                ->select(['suspects.*'])
                ->distinct()
                ->where('crime.location_id', '=', $this->id)
                ->get();
}

public function getSuspectsAttribute()
{
    return $this->allSuspects();
}

I mean, I need to retrieve the suspects directly as a colleciton of model for Location. Not the Crimes in that location, but the Suspects in that location.

I have updated my reply to reflect that

^ Yes it worked now, it retrieves the suspects from each of the crimes for that location. The problem is, it's not distinct. It returns duplicate suspect.

Thanks for your response by the way! If I'm able to get the suspects' list in a distinct way (like in my own solution), I could use your solution as an alternative. :D

Change the method as:

public function suspects()
{
    return $this->crimes->flatMap(function ($crime) {
        return $crime->suspects;
    })->unique('id');
}

^ close enough. the suspects model now returns the pivot field:

pivot: {
    crime_committed_id: "3",
    suspect_id: "2"
}

Thus, making it un-unique

Wait, nevermind the pivot, solved it by hiding it:

protected $hidden = ['pivot'];

in suspect class. But still it's not becoming unique, it still returns duplicate

All right! Solved it using

    return $this->crimes->flatMap(function ($crime) {
        return $crime->suspects;
    })->unique('id');

I prefer this because it returns the Eloquent model I've made. Thank so much for your help @rumm.an

Ow yeah! forgot that unique accepts attributes too. updated